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Edit File: compiler.py
# sql/compiler.py # Copyright (C) 2005-2024 the SQLAlchemy authors and contributors # <see AUTHORS file> # # This module is part of SQLAlchemy and is released under # the MIT License: https://www.opensource.org/licenses/mit-license.php """Base SQL and DDL compiler implementations. Classes provided include: :class:`.compiler.SQLCompiler` - renders SQL strings :class:`.compiler.DDLCompiler` - renders DDL (data definition language) strings :class:`.compiler.GenericTypeCompiler` - renders type specification strings. To generate user-defined SQL strings, see :doc:`/ext/compiler`. """ import collections import contextlib import itertools import operator import re from . import base from . import coercions from . import crud from . import elements from . import functions from . import operators from . import schema from . import selectable from . import sqltypes from . import util as sql_util from .base import NO_ARG from .base import prefix_anon_map from .elements import quoted_name from .. import exc from .. import util RESERVED_WORDS = set( [ "all", "analyse", "analyze", "and", "any", "array", "as", "asc", "asymmetric", "authorization", "between", "binary", "both", "case", "cast", "check", "collate", "column", "constraint", "create", "cross", "current_date", "current_role", "current_time", "current_timestamp", "current_user", "default", "deferrable", "desc", "distinct", "do", "else", "end", "except", "false", "for", "foreign", "freeze", "from", "full", "grant", "group", "having", "ilike", "in", "initially", "inner", "intersect", "into", "is", "isnull", "join", "leading", "left", "like", "limit", "localtime", "localtimestamp", "natural", "new", "not", "notnull", "null", "off", "offset", "old", "on", "only", "or", "order", "outer", "overlaps", "placing", "primary", "references", "right", "select", "session_user", "set", "similar", "some", "symmetric", "table", "then", "to", "trailing", "true", "union", "unique", "user", "using", "verbose", "when", "where", ] ) LEGAL_CHARACTERS = re.compile(r"^[A-Z0-9_$]+$", re.I) LEGAL_CHARACTERS_PLUS_SPACE = re.compile(r"^[A-Z0-9_ $]+$", re.I) ILLEGAL_INITIAL_CHARACTERS = {str(x) for x in range(0, 10)}.union(["$"]) FK_ON_DELETE = re.compile( r"^(?:RESTRICT|CASCADE|SET NULL|NO ACTION|SET DEFAULT)$", re.I ) FK_ON_UPDATE = re.compile( r"^(?:RESTRICT|CASCADE|SET NULL|NO ACTION|SET DEFAULT)$", re.I ) FK_INITIALLY = re.compile(r"^(?:DEFERRED|IMMEDIATE)$", re.I) BIND_PARAMS = re.compile(r"(?<![:\w\$\x5c]):([\w\$]+)(?![:\w\$])", re.UNICODE) BIND_PARAMS_ESC = re.compile(r"\x5c(:[\w\$]*)(?![:\w\$])", re.UNICODE) BIND_TEMPLATES = { "pyformat": "%%(%(name)s)s", "qmark": "?", "format": "%%s", "numeric": ":[_POSITION]", "named": ":%(name)s", } _BIND_TRANSLATE_RE = re.compile(r"[%\(\):\[\] ]") _BIND_TRANSLATE_CHARS = dict(zip("%():[] ", "PAZC___")) OPERATORS = { # binary operators.and_: " AND ", operators.or_: " OR ", operators.add: " + ", operators.mul: " * ", operators.sub: " - ", operators.div: " / ", operators.mod: " % ", operators.truediv: " / ", operators.neg: "-", operators.lt: " < ", operators.le: " <= ", operators.ne: " != ", operators.gt: " > ", operators.ge: " >= ", operators.eq: " = ", operators.is_distinct_from: " IS DISTINCT FROM ", operators.is_not_distinct_from: " IS NOT DISTINCT FROM ", operators.concat_op: " || ", operators.match_op: " MATCH ", operators.not_match_op: " NOT MATCH ", operators.in_op: " IN ", operators.not_in_op: " NOT IN ", operators.comma_op: ", ", operators.from_: " FROM ", operators.as_: " AS ", operators.is_: " IS ", operators.is_not: " IS NOT ", operators.collate: " COLLATE ", # unary operators.exists: "EXISTS ", operators.distinct_op: "DISTINCT ", operators.inv: "NOT ", operators.any_op: "ANY ", operators.all_op: "ALL ", # modifiers operators.desc_op: " DESC", operators.asc_op: " ASC", operators.nulls_first_op: " NULLS FIRST", operators.nulls_last_op: " NULLS LAST", } FUNCTIONS = { functions.coalesce: "coalesce", functions.current_date: "CURRENT_DATE", functions.current_time: "CURRENT_TIME", functions.current_timestamp: "CURRENT_TIMESTAMP", functions.current_user: "CURRENT_USER", functions.localtime: "LOCALTIME", functions.localtimestamp: "LOCALTIMESTAMP", functions.random: "random", functions.sysdate: "sysdate", functions.session_user: "SESSION_USER", functions.user: "USER", functions.cube: "CUBE", functions.rollup: "ROLLUP", functions.grouping_sets: "GROUPING SETS", } EXTRACT_MAP = { "month": "month", "day": "day", "year": "year", "second": "second", "hour": "hour", "doy": "doy", "minute": "minute", "quarter": "quarter", "dow": "dow", "week": "week", "epoch": "epoch", "milliseconds": "milliseconds", "microseconds": "microseconds", "timezone_hour": "timezone_hour", "timezone_minute": "timezone_minute", } COMPOUND_KEYWORDS = { selectable.CompoundSelect.UNION: "UNION", selectable.CompoundSelect.UNION_ALL: "UNION ALL", selectable.CompoundSelect.EXCEPT: "EXCEPT", selectable.CompoundSelect.EXCEPT_ALL: "EXCEPT ALL", selectable.CompoundSelect.INTERSECT: "INTERSECT", selectable.CompoundSelect.INTERSECT_ALL: "INTERSECT ALL", } RM_RENDERED_NAME = 0 RM_NAME = 1 RM_OBJECTS = 2 RM_TYPE = 3 ExpandedState = collections.namedtuple( "ExpandedState", [ "statement", "additional_parameters", "processors", "positiontup", "parameter_expansion", ], ) NO_LINTING = util.symbol("NO_LINTING", "Disable all linting.", canonical=0) COLLECT_CARTESIAN_PRODUCTS = util.symbol( "COLLECT_CARTESIAN_PRODUCTS", "Collect data on FROMs and cartesian products and gather " "into 'self.from_linter'", canonical=1, ) WARN_LINTING = util.symbol( "WARN_LINTING", "Emit warnings for linters that find problems", canonical=2 ) FROM_LINTING = util.symbol( "FROM_LINTING", "Warn for cartesian products; " "combines COLLECT_CARTESIAN_PRODUCTS and WARN_LINTING", canonical=COLLECT_CARTESIAN_PRODUCTS | WARN_LINTING, ) class FromLinter(collections.namedtuple("FromLinter", ["froms", "edges"])): def lint(self, start=None): froms = self.froms if not froms: return None, None edges = set(self.edges) the_rest = set(froms) if start is not None: start_with = start the_rest.remove(start_with) else: start_with = the_rest.pop() stack = collections.deque([start_with]) while stack and the_rest: node = stack.popleft() the_rest.discard(node) # comparison of nodes in edges here is based on hash equality, as # there are "annotated" elements that match the non-annotated ones. # to remove the need for in-python hash() calls, use native # containment routines (e.g. "node in edge", "edge.index(node)") to_remove = {edge for edge in edges if node in edge} # appendleft the node in each edge that is not # the one that matched. stack.extendleft(edge[not edge.index(node)] for edge in to_remove) edges.difference_update(to_remove) # FROMS left over? boom if the_rest: return the_rest, start_with else: return None, None def warn(self): the_rest, start_with = self.lint() # FROMS left over? boom if the_rest: froms = the_rest if froms: template = ( "SELECT statement has a cartesian product between " "FROM element(s) {froms} and " 'FROM element "{start}". Apply join condition(s) ' "between each element to resolve." ) froms_str = ", ".join( '"{elem}"'.format(elem=self.froms[from_]) for from_ in froms ) message = template.format( froms=froms_str, start=self.froms[start_with] ) util.warn(message) class Compiled(object): """Represent a compiled SQL or DDL expression. The ``__str__`` method of the ``Compiled`` object should produce the actual text of the statement. ``Compiled`` objects are specific to their underlying database dialect, and also may or may not be specific to the columns referenced within a particular set of bind parameters. In no case should the ``Compiled`` object be dependent on the actual values of those bind parameters, even though it may reference those values as defaults. """ _cached_metadata = None _result_columns = None schema_translate_map = None execution_options = util.EMPTY_DICT """ Execution options propagated from the statement. In some cases, sub-elements of the statement can modify these. """ _annotations = util.EMPTY_DICT compile_state = None """Optional :class:`.CompileState` object that maintains additional state used by the compiler. Major executable objects such as :class:`_expression.Insert`, :class:`_expression.Update`, :class:`_expression.Delete`, :class:`_expression.Select` will generate this state when compiled in order to calculate additional information about the object. For the top level object that is to be executed, the state can be stored here where it can also have applicability towards result set processing. .. versionadded:: 1.4 """ dml_compile_state = None """Optional :class:`.CompileState` assigned at the same point that .isinsert, .isupdate, or .isdelete is assigned. This will normally be the same object as .compile_state, with the exception of cases like the :class:`.ORMFromStatementCompileState` object. .. versionadded:: 1.4.40 """ cache_key = None _gen_time = None def __init__( self, dialect, statement, schema_translate_map=None, render_schema_translate=False, compile_kwargs=util.immutabledict(), ): """Construct a new :class:`.Compiled` object. :param dialect: :class:`.Dialect` to compile against. :param statement: :class:`_expression.ClauseElement` to be compiled. :param schema_translate_map: dictionary of schema names to be translated when forming the resultant SQL .. versionadded:: 1.1 .. seealso:: :ref:`schema_translating` :param compile_kwargs: additional kwargs that will be passed to the initial call to :meth:`.Compiled.process`. """ self.dialect = dialect self.preparer = self.dialect.identifier_preparer if schema_translate_map: self.schema_translate_map = schema_translate_map self.preparer = self.preparer._with_schema_translate( schema_translate_map ) if statement is not None: self.statement = statement self.can_execute = statement.supports_execution self._annotations = statement._annotations if self.can_execute: self.execution_options = statement._execution_options self.string = self.process(self.statement, **compile_kwargs) if render_schema_translate: self.string = self.preparer._render_schema_translates( self.string, schema_translate_map ) self._gen_time = util.perf_counter() def _execute_on_connection( self, connection, multiparams, params, execution_options ): if self.can_execute: return connection._execute_compiled( self, multiparams, params, execution_options ) else: raise exc.ObjectNotExecutableError(self.statement) def visit_unsupported_compilation(self, element, err): util.raise_( exc.UnsupportedCompilationError(self, type(element)), replace_context=err, ) @property def sql_compiler(self): """Return a Compiled that is capable of processing SQL expressions. If this compiler is one, it would likely just return 'self'. """ raise NotImplementedError() def process(self, obj, **kwargs): return obj._compiler_dispatch(self, **kwargs) def __str__(self): """Return the string text of the generated SQL or DDL.""" return self.string or "" def construct_params( self, params=None, extracted_parameters=None, escape_names=True ): """Return the bind params for this compiled object. :param params: a dict of string/object pairs whose values will override bind values compiled in to the statement. """ raise NotImplementedError() @property def params(self): """Return the bind params for this compiled object.""" return self.construct_params() class TypeCompiler(util.with_metaclass(util.EnsureKWArgType, object)): """Produces DDL specification for TypeEngine objects.""" ensure_kwarg = r"visit_\w+" def __init__(self, dialect): self.dialect = dialect def process(self, type_, **kw): return type_._compiler_dispatch(self, **kw) def visit_unsupported_compilation(self, element, err, **kw): util.raise_( exc.UnsupportedCompilationError(self, element), replace_context=err, ) # this was a Visitable, but to allow accurate detection of # column elements this is actually a column element class _CompileLabel(elements.ColumnElement): """lightweight label object which acts as an expression.Label.""" __visit_name__ = "label" __slots__ = "element", "name" def __init__(self, col, name, alt_names=()): self.element = col self.name = name self._alt_names = (col,) + alt_names @property def proxy_set(self): return self.element.proxy_set @property def type(self): return self.element.type def self_group(self, **kw): return self class SQLCompiler(Compiled): """Default implementation of :class:`.Compiled`. Compiles :class:`_expression.ClauseElement` objects into SQL strings. """ extract_map = EXTRACT_MAP compound_keywords = COMPOUND_KEYWORDS isdelete = isinsert = isupdate = False """class-level defaults which can be set at the instance level to define if this Compiled instance represents INSERT/UPDATE/DELETE """ isplaintext = False returning = None """holds the "returning" collection of columns if the statement is CRUD and defines returning columns either implicitly or explicitly """ returning_precedes_values = False """set to True classwide to generate RETURNING clauses before the VALUES or WHERE clause (i.e. MSSQL) """ render_table_with_column_in_update_from = False """set to True classwide to indicate the SET clause in a multi-table UPDATE statement should qualify columns with the table name (i.e. MySQL only) """ ansi_bind_rules = False """SQL 92 doesn't allow bind parameters to be used in the columns clause of a SELECT, nor does it allow ambiguous expressions like "? = ?". A compiler subclass can set this flag to False if the target driver/DB enforces this """ _textual_ordered_columns = False """tell the result object that the column names as rendered are important, but they are also "ordered" vs. what is in the compiled object here. As of 1.4.42 this condition is only present when the statement is a TextualSelect, e.g. text("....").columns(...), where it is required that the columns are considered positionally and not by name. """ _ad_hoc_textual = False """tell the result that we encountered text() or '*' constructs in the middle of the result columns, but we also have compiled columns, so if the number of columns in cursor.description does not match how many expressions we have, that means we can't rely on positional at all and should match on name. """ _ordered_columns = True """ if False, means we can't be sure the list of entries in _result_columns is actually the rendered order. Usually True unless using an unordered TextualSelect. """ _loose_column_name_matching = False """tell the result object that the SQL statement is textual, wants to match up to Column objects, and may be using the ._tq_label in the SELECT rather than the base name. """ _numeric_binds = False """ True if paramstyle is "numeric". This paramstyle is trickier than all the others. """ _render_postcompile = False """ whether to render out POSTCOMPILE params during the compile phase. """ insert_single_values_expr = None """When an INSERT is compiled with a single set of parameters inside a VALUES expression, the string is assigned here, where it can be used for insert batching schemes to rewrite the VALUES expression. .. versionadded:: 1.3.8 """ literal_execute_params = frozenset() """bindparameter objects that are rendered as literal values at statement execution time. """ post_compile_params = frozenset() """bindparameter objects that are rendered as bound parameter placeholders at statement execution time. """ escaped_bind_names = util.EMPTY_DICT """Late escaping of bound parameter names that has to be converted to the original name when looking in the parameter dictionary. """ has_out_parameters = False """if True, there are bindparam() objects that have the isoutparam flag set.""" insert_prefetch = update_prefetch = () postfetch_lastrowid = False """if True, and this in insert, use cursor.lastrowid to populate result.inserted_primary_key. """ _cache_key_bind_match = None """a mapping that will relate the BindParameter object we compile to those that are part of the extracted collection of parameters in the cache key, if we were given a cache key. """ _post_compile_pattern = re.compile(r"__\[POSTCOMPILE_(\S+?)(~~.+?~~)?\]") positiontup = None """for a compiled construct that uses a positional paramstyle, will be a sequence of strings, indicating the names of bound parameters in order. This is used in order to render bound parameters in their correct order, and is combined with the :attr:`_sql.Compiled.params` dictionary to render parameters. .. seealso:: :ref:`faq_sql_expression_string` - includes a usage example for debugging use cases. """ positiontup_level = None inline = False def __init__( self, dialect, statement, cache_key=None, column_keys=None, for_executemany=False, linting=NO_LINTING, **kwargs ): """Construct a new :class:`.SQLCompiler` object. :param dialect: :class:`.Dialect` to be used :param statement: :class:`_expression.ClauseElement` to be compiled :param column_keys: a list of column names to be compiled into an INSERT or UPDATE statement. :param for_executemany: whether INSERT / UPDATE statements should expect that they are to be invoked in an "executemany" style, which may impact how the statement will be expected to return the values of defaults and autoincrement / sequences and similar. Depending on the backend and driver in use, support for retrieving these values may be disabled which means SQL expressions may be rendered inline, RETURNING may not be rendered, etc. :param kwargs: additional keyword arguments to be consumed by the superclass. """ self.column_keys = column_keys self.cache_key = cache_key if cache_key: self._cache_key_bind_match = ckbm = { b.key: b for b in cache_key[1] } ckbm.update({b: [b] for b in cache_key[1]}) # compile INSERT/UPDATE defaults/sequences to expect executemany # style execution, which may mean no pre-execute of defaults, # or no RETURNING self.for_executemany = for_executemany self.linting = linting # a dictionary of bind parameter keys to BindParameter # instances. self.binds = {} # a dictionary of BindParameter instances to "compiled" names # that are actually present in the generated SQL self.bind_names = util.column_dict() # stack which keeps track of nested SELECT statements self.stack = [] # relates label names in the final SQL to a tuple of local # column/label name, ColumnElement object (if any) and # TypeEngine. CursorResult uses this for type processing and # column targeting self._result_columns = [] # true if the paramstyle is positional self.positional = dialect.positional if self.positional: self.positiontup_level = {} self.positiontup = [] self._numeric_binds = dialect.paramstyle == "numeric" self.bindtemplate = BIND_TEMPLATES[dialect.paramstyle] self.ctes = None self.label_length = ( dialect.label_length or dialect.max_identifier_length ) # a map which tracks "anonymous" identifiers that are created on # the fly here self.anon_map = prefix_anon_map() # a map which tracks "truncated" names based on # dialect.label_length or dialect.max_identifier_length self.truncated_names = {} Compiled.__init__(self, dialect, statement, **kwargs) if self.isinsert or self.isupdate or self.isdelete: if statement._returning: self.returning = statement._returning if self.isinsert or self.isupdate: if statement._inline: self.inline = True elif self.for_executemany and ( not self.isinsert or ( self.dialect.insert_executemany_returning and statement._return_defaults ) ): self.inline = True if self.positional and self._numeric_binds: self._apply_numbered_params() if self._render_postcompile: self._process_parameters_for_postcompile(_populate_self=True) @property def current_executable(self): """Return the current 'executable' that is being compiled. This is currently the :class:`_sql.Select`, :class:`_sql.Insert`, :class:`_sql.Update`, :class:`_sql.Delete`, :class:`_sql.CompoundSelect` object that is being compiled. Specifically it's assigned to the ``self.stack`` list of elements. When a statement like the above is being compiled, it normally is also assigned to the ``.statement`` attribute of the :class:`_sql.Compiler` object. However, all SQL constructs are ultimately nestable, and this attribute should never be consulted by a ``visit_`` method, as it is not guaranteed to be assigned nor guaranteed to correspond to the current statement being compiled. .. versionadded:: 1.3.21 For compatibility with previous versions, use the following recipe:: statement = getattr(self, "current_executable", False) if statement is False: statement = self.stack[-1]["selectable"] For versions 1.4 and above, ensure only .current_executable is used; the format of "self.stack" may change. """ try: return self.stack[-1]["selectable"] except IndexError as ie: util.raise_( IndexError("Compiler does not have a stack entry"), replace_context=ie, ) @property def prefetch(self): return list(self.insert_prefetch + self.update_prefetch) @util.memoized_property def _global_attributes(self): return {} @util.memoized_instancemethod def _init_cte_state(self): """Initialize collections related to CTEs only if a CTE is located, to save on the overhead of these collections otherwise. """ # collect CTEs to tack on top of a SELECT # To store the query to print - Dict[cte, text_query] self.ctes = util.OrderedDict() # Detect same CTE references - Dict[(level, name), cte] # Level is required for supporting nesting self.ctes_by_level_name = {} # To retrieve key/level in ctes_by_level_name - # Dict[cte_reference, (level, cte_name)] self.level_name_by_cte = {} self.ctes_recursive = False if self.positional: self.cte_positional = {} self.cte_level = {} self.cte_order = collections.defaultdict(list) @contextlib.contextmanager def _nested_result(self): """special API to support the use case of 'nested result sets'""" result_columns, ordered_columns = ( self._result_columns, self._ordered_columns, ) self._result_columns, self._ordered_columns = [], False try: if self.stack: entry = self.stack[-1] entry["need_result_map_for_nested"] = True else: entry = None yield self._result_columns, self._ordered_columns finally: if entry: entry.pop("need_result_map_for_nested") self._result_columns, self._ordered_columns = ( result_columns, ordered_columns, ) def _apply_numbered_params(self): poscount = itertools.count(1) self.string = re.sub( r"\[_POSITION\]", lambda m: str(util.next(poscount)), self.string ) @util.memoized_property def _bind_processors(self): return dict( ( key, value, ) for key, value in ( ( self.bind_names[bindparam], bindparam.type._cached_bind_processor(self.dialect) if not bindparam.type._is_tuple_type else tuple( elem_type._cached_bind_processor(self.dialect) for elem_type in bindparam.type.types ), ) for bindparam in self.bind_names ) if value is not None ) def is_subquery(self): return len(self.stack) > 1 @property def sql_compiler(self): return self def construct_params( self, params=None, _group_number=None, _check=True, extracted_parameters=None, escape_names=True, ): """return a dictionary of bind parameter keys and values""" has_escaped_names = escape_names and bool(self.escaped_bind_names) if extracted_parameters: # related the bound parameters collected in the original cache key # to those collected in the incoming cache key. They will not have # matching names but they will line up positionally in the same # way. The parameters present in self.bind_names may be clones of # these original cache key params in the case of DML but the .key # will be guaranteed to match. try: orig_extracted = self.cache_key[1] except TypeError as err: util.raise_( exc.CompileError( "This compiled object has no original cache key; " "can't pass extracted_parameters to construct_params" ), replace_context=err, ) ckbm = self._cache_key_bind_match resolved_extracted = { bind: extracted for b, extracted in zip(orig_extracted, extracted_parameters) for bind in ckbm[b] } else: resolved_extracted = None if params: pd = {} for bindparam, name in self.bind_names.items(): escaped_name = ( self.escaped_bind_names.get(name, name) if has_escaped_names else name ) if bindparam.key in params: pd[escaped_name] = params[bindparam.key] elif name in params: pd[escaped_name] = params[name] elif _check and bindparam.required: if _group_number: raise exc.InvalidRequestError( "A value is required for bind parameter %r, " "in parameter group %d" % (bindparam.key, _group_number), code="cd3x", ) else: raise exc.InvalidRequestError( "A value is required for bind parameter %r" % bindparam.key, code="cd3x", ) else: if resolved_extracted: value_param = resolved_extracted.get( bindparam, bindparam ) else: value_param = bindparam if bindparam.callable: pd[escaped_name] = value_param.effective_value else: pd[escaped_name] = value_param.value return pd else: pd = {} for bindparam, name in self.bind_names.items(): escaped_name = ( self.escaped_bind_names.get(name, name) if has_escaped_names else name ) if _check and bindparam.required: if _group_number: raise exc.InvalidRequestError( "A value is required for bind parameter %r, " "in parameter group %d" % (bindparam.key, _group_number), code="cd3x", ) else: raise exc.InvalidRequestError( "A value is required for bind parameter %r" % bindparam.key, code="cd3x", ) if resolved_extracted: value_param = resolved_extracted.get(bindparam, bindparam) else: value_param = bindparam if bindparam.callable: pd[escaped_name] = value_param.effective_value else: pd[escaped_name] = value_param.value return pd @util.memoized_instancemethod def _get_set_input_sizes_lookup( self, include_types=None, exclude_types=None ): if not hasattr(self, "bind_names"): return None dialect = self.dialect dbapi = self.dialect.dbapi # _unwrapped_dialect_impl() is necessary so that we get the # correct dialect type for a custom TypeDecorator, or a Variant, # which is also a TypeDecorator. Special types like Interval, # that use TypeDecorator but also might be mapped directly # for a dialect impl, also subclass Emulated first which overrides # this behavior in those cases to behave like the default. if include_types is None and exclude_types is None: def _lookup_type(typ): dbtype = typ.dialect_impl(dialect).get_dbapi_type(dbapi) return dbtype else: def _lookup_type(typ): # note we get dbtype from the possibly TypeDecorator-wrapped # dialect_impl, but the dialect_impl itself that we use for # include/exclude is the unwrapped version. dialect_impl = typ._unwrapped_dialect_impl(dialect) dbtype = typ.dialect_impl(dialect).get_dbapi_type(dbapi) if ( dbtype is not None and ( exclude_types is None or dbtype not in exclude_types and type(dialect_impl) not in exclude_types ) and ( include_types is None or dbtype in include_types or type(dialect_impl) in include_types ) ): return dbtype else: return None inputsizes = {} literal_execute_params = self.literal_execute_params for bindparam in self.bind_names: if bindparam in literal_execute_params: continue if bindparam.type._is_tuple_type: inputsizes[bindparam] = [ _lookup_type(typ) for typ in bindparam.type.types ] else: inputsizes[bindparam] = _lookup_type(bindparam.type) return inputsizes @property def params(self): """Return the bind param dictionary embedded into this compiled object, for those values that are present. .. seealso:: :ref:`faq_sql_expression_string` - includes a usage example for debugging use cases. """ return self.construct_params(_check=False) def _process_parameters_for_postcompile( self, parameters=None, _populate_self=False ): """handle special post compile parameters. These include: * "expanding" parameters -typically IN tuples that are rendered on a per-parameter basis for an otherwise fixed SQL statement string. * literal_binds compiled with the literal_execute flag. Used for things like SQL Server "TOP N" where the driver does not accommodate N as a bound parameter. """ if parameters is None: parameters = self.construct_params(escape_names=False) expanded_parameters = {} if self.positional: positiontup = [] else: positiontup = None processors = self._bind_processors new_processors = {} if self.positional and self._numeric_binds: # I'm not familiar with any DBAPI that uses 'numeric'. # strategy would likely be to make use of numbers greater than # the highest number present; then for expanding parameters, # append them to the end of the parameter list. that way # we avoid having to renumber all the existing parameters. raise NotImplementedError( "'post-compile' bind parameters are not supported with " "the 'numeric' paramstyle at this time." ) replacement_expressions = {} to_update_sets = {} # notes: # *unescaped* parameter names in: # self.bind_names, self.binds, self._bind_processors # # *escaped* parameter names in: # construct_params(), replacement_expressions for name in ( self.positiontup if self.positional else self.bind_names.values() ): escaped_name = ( self.escaped_bind_names.get(name, name) if self.escaped_bind_names else name ) parameter = self.binds[name] if parameter in self.literal_execute_params: if escaped_name not in replacement_expressions: replacement_expressions[ escaped_name ] = self.render_literal_bindparam( parameter, render_literal_value=parameters.pop(escaped_name), ) continue if parameter in self.post_compile_params: if escaped_name in replacement_expressions: to_update = to_update_sets[escaped_name] else: # we are removing the parameter from parameters # because it is a list value, which is not expected by # TypeEngine objects that would otherwise be asked to # process it. the single name is being replaced with # individual numbered parameters for each value in the # param. # # note we are also inserting *escaped* parameter names # into the given dictionary. default dialect will # use these param names directly as they will not be # in the escaped_bind_names dictionary. values = parameters.pop(name) leep = self._literal_execute_expanding_parameter to_update, replacement_expr = leep( escaped_name, parameter, values ) to_update_sets[escaped_name] = to_update replacement_expressions[escaped_name] = replacement_expr if not parameter.literal_execute: parameters.update(to_update) if parameter.type._is_tuple_type: new_processors.update( ( "%s_%s_%s" % (name, i, j), processors[name][j - 1], ) for i, tuple_element in enumerate(values, 1) for j, value in enumerate(tuple_element, 1) if name in processors and processors[name][j - 1] is not None ) else: new_processors.update( (key, processors[name]) for key, value in to_update if name in processors ) if self.positional: positiontup.extend(name for name, value in to_update) expanded_parameters[name] = [ expand_key for expand_key, value in to_update ] elif self.positional: positiontup.append(name) def process_expanding(m): key = m.group(1) expr = replacement_expressions[key] # if POSTCOMPILE included a bind_expression, render that # around each element if m.group(2): tok = m.group(2).split("~~") be_left, be_right = tok[1], tok[3] expr = ", ".join( "%s%s%s" % (be_left, exp, be_right) for exp in expr.split(", ") ) return expr statement = re.sub( self._post_compile_pattern, process_expanding, self.string, ) expanded_state = ExpandedState( statement, parameters, new_processors, positiontup, expanded_parameters, ) if _populate_self: # this is for the "render_postcompile" flag, which is not # otherwise used internally and is for end-user debugging and # special use cases. self.string = expanded_state.statement self._bind_processors.update(expanded_state.processors) self.positiontup = expanded_state.positiontup self.post_compile_params = frozenset() for key in expanded_state.parameter_expansion: bind = self.binds.pop(key) self.bind_names.pop(bind) for value, expanded_key in zip( bind.value, expanded_state.parameter_expansion[key] ): self.binds[expanded_key] = new_param = bind._with_value( value ) self.bind_names[new_param] = expanded_key return expanded_state @util.preload_module("sqlalchemy.engine.cursor") def _create_result_map(self): """utility method used for unit tests only.""" cursor = util.preloaded.engine_cursor return cursor.CursorResultMetaData._create_description_match_map( self._result_columns ) @util.memoized_property def _within_exec_param_key_getter(self): getter = self._key_getters_for_crud_column[2] return getter @util.memoized_property @util.preload_module("sqlalchemy.engine.result") def _inserted_primary_key_from_lastrowid_getter(self): result = util.preloaded.engine_result param_key_getter = self._within_exec_param_key_getter table = self.statement.table getters = [ (operator.methodcaller("get", param_key_getter(col), None), col) for col in table.primary_key ] autoinc_col = table._autoincrement_column if autoinc_col is not None: # apply type post processors to the lastrowid proc = autoinc_col.type._cached_result_processor( self.dialect, None ) else: proc = None row_fn = result.result_tuple([col.key for col in table.primary_key]) def get(lastrowid, parameters): """given cursor.lastrowid value and the parameters used for INSERT, return a "row" that represents the primary key, either by using the "lastrowid" or by extracting values from the parameters that were sent along with the INSERT. """ if proc is not None: lastrowid = proc(lastrowid) if lastrowid is None: return row_fn(getter(parameters) for getter, col in getters) else: return row_fn( lastrowid if col is autoinc_col else getter(parameters) for getter, col in getters ) return get @util.memoized_property @util.preload_module("sqlalchemy.engine.result") def _inserted_primary_key_from_returning_getter(self): result = util.preloaded.engine_result param_key_getter = self._within_exec_param_key_getter table = self.statement.table ret = {col: idx for idx, col in enumerate(self.returning)} getters = [ (operator.itemgetter(ret[col]), True) if col in ret else ( operator.methodcaller("get", param_key_getter(col), None), False, ) for col in table.primary_key ] row_fn = result.result_tuple([col.key for col in table.primary_key]) def get(row, parameters): return row_fn( getter(row) if use_row else getter(parameters) for getter, use_row in getters ) return get def default_from(self): """Called when a SELECT statement has no froms, and no FROM clause is to be appended. Gives Oracle a chance to tack on a ``FROM DUAL`` to the string output. """ return "" def visit_grouping(self, grouping, asfrom=False, **kwargs): return "(" + grouping.element._compiler_dispatch(self, **kwargs) + ")" def visit_select_statement_grouping(self, grouping, **kwargs): return "(" + grouping.element._compiler_dispatch(self, **kwargs) + ")" def visit_label_reference( self, element, within_columns_clause=False, **kwargs ): if self.stack and self.dialect.supports_simple_order_by_label: compile_state = self.stack[-1]["compile_state"] ( with_cols, only_froms, only_cols, ) = compile_state._label_resolve_dict if within_columns_clause: resolve_dict = only_froms else: resolve_dict = only_cols # this can be None in the case that a _label_reference() # were subject to a replacement operation, in which case # the replacement of the Label element may have changed # to something else like a ColumnClause expression. order_by_elem = element.element._order_by_label_element if ( order_by_elem is not None and order_by_elem.name in resolve_dict and order_by_elem.shares_lineage( resolve_dict[order_by_elem.name] ) ): kwargs[ "render_label_as_label" ] = element.element._order_by_label_element return self.process( element.element, within_columns_clause=within_columns_clause, **kwargs ) def visit_textual_label_reference( self, element, within_columns_clause=False, **kwargs ): if not self.stack: # compiling the element outside of the context of a SELECT return self.process(element._text_clause) compile_state = self.stack[-1]["compile_state"] with_cols, only_froms, only_cols = compile_state._label_resolve_dict try: if within_columns_clause: col = only_froms[element.element] else: col = with_cols[element.element] except KeyError as err: coercions._no_text_coercion( element.element, extra=( "Can't resolve label reference for ORDER BY / " "GROUP BY / DISTINCT etc." ), exc_cls=exc.CompileError, err=err, ) else: kwargs["render_label_as_label"] = col return self.process( col, within_columns_clause=within_columns_clause, **kwargs ) def visit_label( self, label, add_to_result_map=None, within_label_clause=False, within_columns_clause=False, render_label_as_label=None, result_map_targets=(), **kw ): # only render labels within the columns clause # or ORDER BY clause of a select. dialect-specific compilers # can modify this behavior. render_label_with_as = ( within_columns_clause and not within_label_clause ) render_label_only = render_label_as_label is label if render_label_only or render_label_with_as: if isinstance(label.name, elements._truncated_label): labelname = self._truncated_identifier("colident", label.name) else: labelname = label.name if render_label_with_as: if add_to_result_map is not None: add_to_result_map( labelname, label.name, (label, labelname) + label._alt_names + result_map_targets, label.type, ) return ( label.element._compiler_dispatch( self, within_columns_clause=True, within_label_clause=True, **kw ) + OPERATORS[operators.as_] + self.preparer.format_label(label, labelname) ) elif render_label_only: return self.preparer.format_label(label, labelname) else: return label.element._compiler_dispatch( self, within_columns_clause=False, **kw ) def _fallback_column_name(self, column): raise exc.CompileError( "Cannot compile Column object until " "its 'name' is assigned." ) def visit_lambda_element(self, element, **kw): sql_element = element._resolved return self.process(sql_element, **kw) def visit_column( self, column, add_to_result_map=None, include_table=True, result_map_targets=(), **kwargs ): name = orig_name = column.name if name is None: name = self._fallback_column_name(column) is_literal = column.is_literal if not is_literal and isinstance(name, elements._truncated_label): name = self._truncated_identifier("colident", name) if add_to_result_map is not None: targets = (column, name, column.key) + result_map_targets if column._tq_label: targets += (column._tq_label,) add_to_result_map(name, orig_name, targets, column.type) if is_literal: # note we are not currently accommodating for # literal_column(quoted_name('ident', True)) here name = self.escape_literal_column(name) else: name = self.preparer.quote(name) table = column.table if table is None or not include_table or not table.named_with_column: return name else: effective_schema = self.preparer.schema_for_object(table) if effective_schema: schema_prefix = ( self.preparer.quote_schema(effective_schema) + "." ) else: schema_prefix = "" tablename = table.name if isinstance(tablename, elements._truncated_label): tablename = self._truncated_identifier("alias", tablename) return schema_prefix + self.preparer.quote(tablename) + "." + name def visit_collation(self, element, **kw): return self.preparer.format_collation(element.collation) def visit_fromclause(self, fromclause, **kwargs): return fromclause.name def visit_index(self, index, **kwargs): return index.name def visit_typeclause(self, typeclause, **kw): kw["type_expression"] = typeclause kw["identifier_preparer"] = self.preparer return self.dialect.type_compiler.process(typeclause.type, **kw) def post_process_text(self, text): if self.preparer._double_percents: text = text.replace("%", "%%") return text def escape_literal_column(self, text): if self.preparer._double_percents: text = text.replace("%", "%%") return text def visit_textclause(self, textclause, add_to_result_map=None, **kw): def do_bindparam(m): name = m.group(1) if name in textclause._bindparams: return self.process(textclause._bindparams[name], **kw) else: return self.bindparam_string(name, **kw) if not self.stack: self.isplaintext = True if add_to_result_map: # text() object is present in the columns clause of a # select(). Add a no-name entry to the result map so that # row[text()] produces a result add_to_result_map(None, None, (textclause,), sqltypes.NULLTYPE) # un-escape any \:params return BIND_PARAMS_ESC.sub( lambda m: m.group(1), BIND_PARAMS.sub( do_bindparam, self.post_process_text(textclause.text) ), ) def visit_textual_select( self, taf, compound_index=None, asfrom=False, **kw ): toplevel = not self.stack entry = self._default_stack_entry if toplevel else self.stack[-1] new_entry = { "correlate_froms": set(), "asfrom_froms": set(), "selectable": taf, } self.stack.append(new_entry) if taf._independent_ctes: for cte in taf._independent_ctes: cte._compiler_dispatch(self, **kw) populate_result_map = ( toplevel or ( compound_index == 0 and entry.get("need_result_map_for_compound", False) ) or entry.get("need_result_map_for_nested", False) ) if populate_result_map: self._ordered_columns = ( self._textual_ordered_columns ) = taf.positional # enable looser result column matching when the SQL text links to # Column objects by name only self._loose_column_name_matching = not taf.positional and bool( taf.column_args ) for c in taf.column_args: self.process( c, within_columns_clause=True, add_to_result_map=self._add_to_result_map, ) text = self.process(taf.element, **kw) if self.ctes: nesting_level = len(self.stack) if not toplevel else None text = ( self._render_cte_clause( nesting_level=nesting_level, visiting_cte=kw.get("visiting_cte"), ) + text ) self.stack.pop(-1) return text def visit_null(self, expr, **kw): return "NULL" def visit_true(self, expr, **kw): if self.dialect.supports_native_boolean: return "true" else: return "1" def visit_false(self, expr, **kw): if self.dialect.supports_native_boolean: return "false" else: return "0" def _generate_delimited_list(self, elements, separator, **kw): return separator.join( s for s in (c._compiler_dispatch(self, **kw) for c in elements) if s ) def _generate_delimited_and_list(self, clauses, **kw): lcc, clauses = elements.BooleanClauseList._process_clauses_for_boolean( operators.and_, elements.True_._singleton, elements.False_._singleton, clauses, ) if lcc == 1: return clauses[0]._compiler_dispatch(self, **kw) else: separator = OPERATORS[operators.and_] return separator.join( s for s in (c._compiler_dispatch(self, **kw) for c in clauses) if s ) def visit_tuple(self, clauselist, **kw): return "(%s)" % self.visit_clauselist(clauselist, **kw) def visit_clauselist(self, clauselist, **kw): sep = clauselist.operator if sep is None: sep = " " else: sep = OPERATORS[clauselist.operator] return self._generate_delimited_list(clauselist.clauses, sep, **kw) def visit_case(self, clause, **kwargs): x = "CASE " if clause.value is not None: x += clause.value._compiler_dispatch(self, **kwargs) + " " for cond, result in clause.whens: x += ( "WHEN " + cond._compiler_dispatch(self, **kwargs) + " THEN " + result._compiler_dispatch(self, **kwargs) + " " ) if clause.else_ is not None: x += ( "ELSE " + clause.else_._compiler_dispatch(self, **kwargs) + " " ) x += "END" return x def visit_type_coerce(self, type_coerce, **kw): return type_coerce.typed_expression._compiler_dispatch(self, **kw) def visit_cast(self, cast, **kwargs): return "CAST(%s AS %s)" % ( cast.clause._compiler_dispatch(self, **kwargs), cast.typeclause._compiler_dispatch(self, **kwargs), ) def _format_frame_clause(self, range_, **kw): return "%s AND %s" % ( "UNBOUNDED PRECEDING" if range_[0] is elements.RANGE_UNBOUNDED else "CURRENT ROW" if range_[0] is elements.RANGE_CURRENT else "%s PRECEDING" % (self.process(elements.literal(abs(range_[0])), **kw),) if range_[0] < 0 else "%s FOLLOWING" % (self.process(elements.literal(range_[0]), **kw),), "UNBOUNDED FOLLOWING" if range_[1] is elements.RANGE_UNBOUNDED else "CURRENT ROW" if range_[1] is elements.RANGE_CURRENT else "%s PRECEDING" % (self.process(elements.literal(abs(range_[1])), **kw),) if range_[1] < 0 else "%s FOLLOWING" % (self.process(elements.literal(range_[1]), **kw),), ) def visit_over(self, over, **kwargs): text = over.element._compiler_dispatch(self, **kwargs) if over.range_: range_ = "RANGE BETWEEN %s" % self._format_frame_clause( over.range_, **kwargs ) elif over.rows: range_ = "ROWS BETWEEN %s" % self._format_frame_clause( over.rows, **kwargs ) else: range_ = None return "%s OVER (%s)" % ( text, " ".join( [ "%s BY %s" % (word, clause._compiler_dispatch(self, **kwargs)) for word, clause in ( ("PARTITION", over.partition_by), ("ORDER", over.order_by), ) if clause is not None and len(clause) ] + ([range_] if range_ else []) ), ) def visit_withingroup(self, withingroup, **kwargs): return "%s WITHIN GROUP (ORDER BY %s)" % ( withingroup.element._compiler_dispatch(self, **kwargs), withingroup.order_by._compiler_dispatch(self, **kwargs), ) def visit_funcfilter(self, funcfilter, **kwargs): return "%s FILTER (WHERE %s)" % ( funcfilter.func._compiler_dispatch(self, **kwargs), funcfilter.criterion._compiler_dispatch(self, **kwargs), ) def visit_extract(self, extract, **kwargs): field = self.extract_map.get(extract.field, extract.field) return "EXTRACT(%s FROM %s)" % ( field, extract.expr._compiler_dispatch(self, **kwargs), ) def visit_scalar_function_column(self, element, **kw): compiled_fn = self.visit_function(element.fn, **kw) compiled_col = self.visit_column(element, **kw) return "(%s).%s" % (compiled_fn, compiled_col) def visit_function(self, func, add_to_result_map=None, **kwargs): if add_to_result_map is not None: add_to_result_map(func.name, func.name, (), func.type) disp = getattr(self, "visit_%s_func" % func.name.lower(), None) if disp: text = disp(func, **kwargs) else: name = FUNCTIONS.get(func._deannotate().__class__, None) if name: if func._has_args: name += "%(expr)s" else: name = func.name name = ( self.preparer.quote(name) if self.preparer._requires_quotes_illegal_chars(name) or isinstance(name, elements.quoted_name) else name ) name = name + "%(expr)s" text = ".".join( [ ( self.preparer.quote(tok) if self.preparer._requires_quotes_illegal_chars(tok) or isinstance(name, elements.quoted_name) else tok ) for tok in func.packagenames ] + [name] ) % {"expr": self.function_argspec(func, **kwargs)} if func._with_ordinality: text += " WITH ORDINALITY" return text def visit_next_value_func(self, next_value, **kw): return self.visit_sequence(next_value.sequence) def visit_sequence(self, sequence, **kw): raise NotImplementedError( "Dialect '%s' does not support sequence increments." % self.dialect.name ) def function_argspec(self, func, **kwargs): return func.clause_expr._compiler_dispatch(self, **kwargs) def visit_compound_select( self, cs, asfrom=False, compound_index=None, **kwargs ): toplevel = not self.stack compile_state = cs._compile_state_factory(cs, self, **kwargs) if toplevel and not self.compile_state: self.compile_state = compile_state compound_stmt = compile_state.statement entry = self._default_stack_entry if toplevel else self.stack[-1] need_result_map = toplevel or ( not compound_index and entry.get("need_result_map_for_compound", False) ) # indicates there is already a CompoundSelect in play if compound_index == 0: entry["select_0"] = cs self.stack.append( { "correlate_froms": entry["correlate_froms"], "asfrom_froms": entry["asfrom_froms"], "selectable": cs, "compile_state": compile_state, "need_result_map_for_compound": need_result_map, } ) if compound_stmt._independent_ctes: for cte in compound_stmt._independent_ctes: cte._compiler_dispatch(self, **kwargs) keyword = self.compound_keywords.get(cs.keyword) text = (" " + keyword + " ").join( ( c._compiler_dispatch( self, asfrom=asfrom, compound_index=i, **kwargs ) for i, c in enumerate(cs.selects) ) ) kwargs["include_table"] = False text += self.group_by_clause(cs, **dict(asfrom=asfrom, **kwargs)) text += self.order_by_clause(cs, **kwargs) if cs._has_row_limiting_clause: text += self._row_limit_clause(cs, **kwargs) if self.ctes: nesting_level = len(self.stack) if not toplevel else None text = ( self._render_cte_clause( nesting_level=nesting_level, include_following_stack=True, visiting_cte=kwargs.get("visiting_cte"), ) + text ) self.stack.pop(-1) return text def _row_limit_clause(self, cs, **kwargs): if cs._fetch_clause is not None: return self.fetch_clause(cs, **kwargs) else: return self.limit_clause(cs, **kwargs) def _get_operator_dispatch(self, operator_, qualifier1, qualifier2): attrname = "visit_%s_%s%s" % ( operator_.__name__, qualifier1, "_" + qualifier2 if qualifier2 else "", ) return getattr(self, attrname, None) def visit_unary( self, unary, add_to_result_map=None, result_map_targets=(), **kw ): if add_to_result_map is not None: result_map_targets += (unary,) kw["add_to_result_map"] = add_to_result_map kw["result_map_targets"] = result_map_targets if unary.operator: if unary.modifier: raise exc.CompileError( "Unary expression does not support operator " "and modifier simultaneously" ) disp = self._get_operator_dispatch( unary.operator, "unary", "operator" ) if disp: return disp(unary, unary.operator, **kw) else: return self._generate_generic_unary_operator( unary, OPERATORS[unary.operator], **kw ) elif unary.modifier: disp = self._get_operator_dispatch( unary.modifier, "unary", "modifier" ) if disp: return disp(unary, unary.modifier, **kw) else: return self._generate_generic_unary_modifier( unary, OPERATORS[unary.modifier], **kw ) else: raise exc.CompileError( "Unary expression has no operator or modifier" ) def visit_is_true_unary_operator(self, element, operator, **kw): if ( element._is_implicitly_boolean or self.dialect.supports_native_boolean ): return self.process(element.element, **kw) else: return "%s = 1" % self.process(element.element, **kw) def visit_is_false_unary_operator(self, element, operator, **kw): if ( element._is_implicitly_boolean or self.dialect.supports_native_boolean ): return "NOT %s" % self.process(element.element, **kw) else: return "%s = 0" % self.process(element.element, **kw) def visit_not_match_op_binary(self, binary, operator, **kw): return "NOT %s" % self.visit_binary( binary, override_operator=operators.match_op ) def visit_not_in_op_binary(self, binary, operator, **kw): # The brackets are required in the NOT IN operation because the empty # case is handled using the form "(col NOT IN (null) OR 1 = 1)". # The presence of the OR makes the brackets required. return "(%s)" % self._generate_generic_binary( binary, OPERATORS[operator], **kw ) def visit_empty_set_op_expr(self, type_, expand_op): if expand_op is operators.not_in_op: if len(type_) > 1: return "(%s)) OR (1 = 1" % ( ", ".join("NULL" for element in type_) ) else: return "NULL) OR (1 = 1" elif expand_op is operators.in_op: if len(type_) > 1: return "(%s)) AND (1 != 1" % ( ", ".join("NULL" for element in type_) ) else: return "NULL) AND (1 != 1" else: return self.visit_empty_set_expr(type_) def visit_empty_set_expr(self, element_types): raise NotImplementedError( "Dialect '%s' does not support empty set expression." % self.dialect.name ) def _literal_execute_expanding_parameter_literal_binds( self, parameter, values, bind_expression_template=None ): typ_dialect_impl = parameter.type._unwrapped_dialect_impl(self.dialect) if not values: # empty IN expression. note we don't need to use # bind_expression_template here because there are no # expressions to render. if typ_dialect_impl._is_tuple_type: replacement_expression = ( "VALUES " if self.dialect.tuple_in_values else "" ) + self.visit_empty_set_op_expr( parameter.type.types, parameter.expand_op ) else: replacement_expression = self.visit_empty_set_op_expr( [parameter.type], parameter.expand_op ) elif typ_dialect_impl._is_tuple_type or ( typ_dialect_impl._isnull and isinstance(values[0], util.collections_abc.Sequence) and not isinstance( values[0], util.string_types + util.binary_types ) ): if typ_dialect_impl._has_bind_expression: raise NotImplementedError( "bind_expression() on TupleType not supported with " "literal_binds" ) replacement_expression = ( "VALUES " if self.dialect.tuple_in_values else "" ) + ", ".join( "(%s)" % ( ", ".join( self.render_literal_value(value, param_type) for value, param_type in zip( tuple_element, parameter.type.types ) ) ) for i, tuple_element in enumerate(values) ) else: if bind_expression_template: post_compile_pattern = self._post_compile_pattern m = post_compile_pattern.search(bind_expression_template) assert m and m.group( 2 ), "unexpected format for expanding parameter" tok = m.group(2).split("~~") be_left, be_right = tok[1], tok[3] replacement_expression = ", ".join( "%s%s%s" % ( be_left, self.render_literal_value(value, parameter.type), be_right, ) for value in values ) else: replacement_expression = ", ".join( self.render_literal_value(value, parameter.type) for value in values ) return (), replacement_expression def _literal_execute_expanding_parameter(self, name, parameter, values): if parameter.literal_execute: return self._literal_execute_expanding_parameter_literal_binds( parameter, values ) typ_dialect_impl = parameter.type._unwrapped_dialect_impl(self.dialect) if not values: to_update = [] if typ_dialect_impl._is_tuple_type: replacement_expression = self.visit_empty_set_op_expr( parameter.type.types, parameter.expand_op ) else: replacement_expression = self.visit_empty_set_op_expr( [parameter.type], parameter.expand_op ) elif typ_dialect_impl._is_tuple_type or ( typ_dialect_impl._isnull and isinstance(values[0], util.collections_abc.Sequence) and not isinstance( values[0], util.string_types + util.binary_types ) ): assert not typ_dialect_impl._is_array to_update = [ ("%s_%s_%s" % (name, i, j), value) for i, tuple_element in enumerate(values, 1) for j, value in enumerate(tuple_element, 1) ] replacement_expression = ( "VALUES " if self.dialect.tuple_in_values else "" ) + ", ".join( "(%s)" % ( ", ".join( self.bindtemplate % {"name": to_update[i * len(tuple_element) + j][0]} for j, value in enumerate(tuple_element) ) ) for i, tuple_element in enumerate(values) ) else: to_update = [ ("%s_%s" % (name, i), value) for i, value in enumerate(values, 1) ] replacement_expression = ", ".join( self.bindtemplate % {"name": key} for key, value in to_update ) return to_update, replacement_expression def visit_binary( self, binary, override_operator=None, eager_grouping=False, from_linter=None, lateral_from_linter=None, **kw ): if from_linter and operators.is_comparison(binary.operator): if lateral_from_linter is not None: enclosing_lateral = kw["enclosing_lateral"] lateral_from_linter.edges.update( itertools.product( binary.left._from_objects + [enclosing_lateral], binary.right._from_objects + [enclosing_lateral], ) ) else: from_linter.edges.update( itertools.product( binary.left._from_objects, binary.right._from_objects ) ) # don't allow "? = ?" to render if ( self.ansi_bind_rules and isinstance(binary.left, elements.BindParameter) and isinstance(binary.right, elements.BindParameter) ): kw["literal_execute"] = True operator_ = override_operator or binary.operator disp = self._get_operator_dispatch(operator_, "binary", None) if disp: return disp(binary, operator_, **kw) else: try: opstring = OPERATORS[operator_] except KeyError as err: util.raise_( exc.UnsupportedCompilationError(self, operator_), replace_context=err, ) else: return self._generate_generic_binary( binary, opstring, from_linter=from_linter, lateral_from_linter=lateral_from_linter, **kw ) def visit_function_as_comparison_op_binary(self, element, operator, **kw): return self.process(element.sql_function, **kw) def visit_mod_binary(self, binary, operator, **kw): if self.preparer._double_percents: return ( self.process(binary.left, **kw) + " %% " + self.process(binary.right, **kw) ) else: return ( self.process(binary.left, **kw) + " % " + self.process(binary.right, **kw) ) def visit_custom_op_binary(self, element, operator, **kw): kw["eager_grouping"] = operator.eager_grouping return self._generate_generic_binary( element, " " + self.escape_literal_column(operator.opstring) + " ", **kw ) def visit_custom_op_unary_operator(self, element, operator, **kw): return self._generate_generic_unary_operator( element, self.escape_literal_column(operator.opstring) + " ", **kw ) def visit_custom_op_unary_modifier(self, element, operator, **kw): return self._generate_generic_unary_modifier( element, " " + self.escape_literal_column(operator.opstring), **kw ) def _generate_generic_binary( self, binary, opstring, eager_grouping=False, **kw ): _in_binary = kw.get("_in_binary", False) kw["_in_binary"] = True kw["_binary_op"] = binary.operator text = ( binary.left._compiler_dispatch( self, eager_grouping=eager_grouping, **kw ) + opstring + binary.right._compiler_dispatch( self, eager_grouping=eager_grouping, **kw ) ) if _in_binary and eager_grouping: text = "(%s)" % text return text def _generate_generic_unary_operator(self, unary, opstring, **kw): return opstring + unary.element._compiler_dispatch(self, **kw) def _generate_generic_unary_modifier(self, unary, opstring, **kw): return unary.element._compiler_dispatch(self, **kw) + opstring @util.memoized_property def _like_percent_literal(self): return elements.literal_column("'%'", type_=sqltypes.STRINGTYPE) def visit_contains_op_binary(self, binary, operator, **kw): binary = binary._clone() percent = self._like_percent_literal binary.right = percent.concat(binary.right).concat(percent) return self.visit_like_op_binary(binary, operator, **kw) def visit_not_contains_op_binary(self, binary, operator, **kw): binary = binary._clone() percent = self._like_percent_literal binary.right = percent.concat(binary.right).concat(percent) return self.visit_not_like_op_binary(binary, operator, **kw) def visit_startswith_op_binary(self, binary, operator, **kw): binary = binary._clone() percent = self._like_percent_literal binary.right = percent._rconcat(binary.right) return self.visit_like_op_binary(binary, operator, **kw) def visit_not_startswith_op_binary(self, binary, operator, **kw): binary = binary._clone() percent = self._like_percent_literal binary.right = percent._rconcat(binary.right) return self.visit_not_like_op_binary(binary, operator, **kw) def visit_endswith_op_binary(self, binary, operator, **kw): binary = binary._clone() percent = self._like_percent_literal binary.right = percent.concat(binary.right) return self.visit_like_op_binary(binary, operator, **kw) def visit_not_endswith_op_binary(self, binary, operator, **kw): binary = binary._clone() percent = self._like_percent_literal binary.right = percent.concat(binary.right) return self.visit_not_like_op_binary(binary, operator, **kw) def visit_like_op_binary(self, binary, operator, **kw): escape = binary.modifiers.get("escape", None) # TODO: use ternary here, not "and"/ "or" return "%s LIKE %s" % ( binary.left._compiler_dispatch(self, **kw), binary.right._compiler_dispatch(self, **kw), ) + ( " ESCAPE " + self.render_literal_value(escape, sqltypes.STRINGTYPE) if escape else "" ) def visit_not_like_op_binary(self, binary, operator, **kw): escape = binary.modifiers.get("escape", None) return "%s NOT LIKE %s" % ( binary.left._compiler_dispatch(self, **kw), binary.right._compiler_dispatch(self, **kw), ) + ( " ESCAPE " + self.render_literal_value(escape, sqltypes.STRINGTYPE) if escape else "" ) def visit_ilike_op_binary(self, binary, operator, **kw): escape = binary.modifiers.get("escape", None) return "lower(%s) LIKE lower(%s)" % ( binary.left._compiler_dispatch(self, **kw), binary.right._compiler_dispatch(self, **kw), ) + ( " ESCAPE " + self.render_literal_value(escape, sqltypes.STRINGTYPE) if escape else "" ) def visit_not_ilike_op_binary(self, binary, operator, **kw): escape = binary.modifiers.get("escape", None) return "lower(%s) NOT LIKE lower(%s)" % ( binary.left._compiler_dispatch(self, **kw), binary.right._compiler_dispatch(self, **kw), ) + ( " ESCAPE " + self.render_literal_value(escape, sqltypes.STRINGTYPE) if escape else "" ) def visit_between_op_binary(self, binary, operator, **kw): symmetric = binary.modifiers.get("symmetric", False) return self._generate_generic_binary( binary, " BETWEEN SYMMETRIC " if symmetric else " BETWEEN ", **kw ) def visit_not_between_op_binary(self, binary, operator, **kw): symmetric = binary.modifiers.get("symmetric", False) return self._generate_generic_binary( binary, " NOT BETWEEN SYMMETRIC " if symmetric else " NOT BETWEEN ", **kw ) def visit_regexp_match_op_binary(self, binary, operator, **kw): raise exc.CompileError( "%s dialect does not support regular expressions" % self.dialect.name ) def visit_not_regexp_match_op_binary(self, binary, operator, **kw): raise exc.CompileError( "%s dialect does not support regular expressions" % self.dialect.name ) def visit_regexp_replace_op_binary(self, binary, operator, **kw): raise exc.CompileError( "%s dialect does not support regular expression replacements" % self.dialect.name ) def visit_bindparam( self, bindparam, within_columns_clause=False, literal_binds=False, skip_bind_expression=False, literal_execute=False, render_postcompile=False, **kwargs ): if not skip_bind_expression: impl = bindparam.type.dialect_impl(self.dialect) if impl._has_bind_expression: bind_expression = impl.bind_expression(bindparam) wrapped = self.process( bind_expression, skip_bind_expression=True, within_columns_clause=within_columns_clause, literal_binds=literal_binds and not bindparam.expanding, literal_execute=literal_execute, render_postcompile=render_postcompile, **kwargs ) if bindparam.expanding: # for postcompile w/ expanding, move the "wrapped" part # of this into the inside m = re.match( r"^(.*)\(__\[POSTCOMPILE_(\S+?)\]\)(.*)$", wrapped ) assert m, "unexpected format for expanding parameter" wrapped = "(__[POSTCOMPILE_%s~~%s~~REPL~~%s~~])" % ( m.group(2), m.group(1), m.group(3), ) if literal_binds: ret = self.render_literal_bindparam( bindparam, within_columns_clause=True, bind_expression_template=wrapped, **kwargs ) return "(%s)" % ret return wrapped if not literal_binds: literal_execute = ( literal_execute or bindparam.literal_execute or (within_columns_clause and self.ansi_bind_rules) ) post_compile = literal_execute or bindparam.expanding else: post_compile = False if literal_binds: ret = self.render_literal_bindparam( bindparam, within_columns_clause=True, **kwargs ) if bindparam.expanding: ret = "(%s)" % ret return ret name = self._truncate_bindparam(bindparam) if name in self.binds: existing = self.binds[name] if existing is not bindparam: if ( (existing.unique or bindparam.unique) and not existing.proxy_set.intersection( bindparam.proxy_set ) and not existing._cloned_set.intersection( bindparam._cloned_set ) ): raise exc.CompileError( "Bind parameter '%s' conflicts with " "unique bind parameter of the same name" % name ) elif existing.expanding != bindparam.expanding: raise exc.CompileError( "Can't reuse bound parameter name '%s' in both " "'expanding' (e.g. within an IN expression) and " "non-expanding contexts. If this parameter is to " "receive a list/array value, set 'expanding=True' on " "it for expressions that aren't IN, otherwise use " "a different parameter name." % (name,) ) elif existing._is_crud or bindparam._is_crud: raise exc.CompileError( "bindparam() name '%s' is reserved " "for automatic usage in the VALUES or SET " "clause of this " "insert/update statement. Please use a " "name other than column name when using bindparam() " "with insert() or update() (for example, 'b_%s')." % (bindparam.key, bindparam.key) ) self.binds[bindparam.key] = self.binds[name] = bindparam # if we are given a cache key that we're going to match against, # relate the bindparam here to one that is most likely present # in the "extracted params" portion of the cache key. this is used # to set up a positional mapping that is used to determine the # correct parameters for a subsequent use of this compiled with # a different set of parameter values. here, we accommodate for # parameters that may have been cloned both before and after the cache # key was been generated. ckbm = self._cache_key_bind_match if ckbm: for bp in bindparam._cloned_set: if bp.key in ckbm: cb = ckbm[bp.key] ckbm[cb].append(bindparam) if bindparam.isoutparam: self.has_out_parameters = True if post_compile: if render_postcompile: self._render_postcompile = True if literal_execute: self.literal_execute_params |= {bindparam} else: self.post_compile_params |= {bindparam} ret = self.bindparam_string( name, post_compile=post_compile, expanding=bindparam.expanding, **kwargs ) if bindparam.expanding: ret = "(%s)" % ret return ret def render_literal_bindparam( self, bindparam, render_literal_value=NO_ARG, bind_expression_template=None, **kw ): if render_literal_value is not NO_ARG: value = render_literal_value else: if bindparam.value is None and bindparam.callable is None: op = kw.get("_binary_op", None) if op and op not in (operators.is_, operators.is_not): util.warn_limited( "Bound parameter '%s' rendering literal NULL in a SQL " "expression; comparisons to NULL should not use " "operators outside of 'is' or 'is not'", (bindparam.key,), ) return self.process(sqltypes.NULLTYPE, **kw) value = bindparam.effective_value if bindparam.expanding: leep = self._literal_execute_expanding_parameter_literal_binds to_update, replacement_expr = leep( bindparam, value, bind_expression_template=bind_expression_template, ) return replacement_expr else: return self.render_literal_value(value, bindparam.type) def render_literal_value(self, value, type_): """Render the value of a bind parameter as a quoted literal. This is used for statement sections that do not accept bind parameters on the target driver/database. This should be implemented by subclasses using the quoting services of the DBAPI. """ processor = type_._cached_literal_processor(self.dialect) if processor: try: return processor(value) except Exception as e: util.raise_( exc.CompileError( "Could not render literal value " '"%s" ' "with datatype " "%s; see parent stack trace for " "more detail." % ( sql_util._repr_single_value(value), type_, ) ), from_=e, ) else: raise exc.CompileError( "No literal value renderer is available for literal value " '"%s" with datatype %s' % (sql_util._repr_single_value(value), type_) ) def _truncate_bindparam(self, bindparam): if bindparam in self.bind_names: return self.bind_names[bindparam] bind_name = bindparam.key if isinstance(bind_name, elements._truncated_label): bind_name = self._truncated_identifier("bindparam", bind_name) # add to bind_names for translation self.bind_names[bindparam] = bind_name return bind_name def _truncated_identifier(self, ident_class, name): if (ident_class, name) in self.truncated_names: return self.truncated_names[(ident_class, name)] anonname = name.apply_map(self.anon_map) if len(anonname) > self.label_length - 6: counter = self.truncated_names.get(ident_class, 1) truncname = ( anonname[0 : max(self.label_length - 6, 0)] + "_" + hex(counter)[2:] ) self.truncated_names[ident_class] = counter + 1 else: truncname = anonname self.truncated_names[(ident_class, name)] = truncname return truncname def _anonymize(self, name): return name % self.anon_map def bindparam_string( self, name, positional_names=None, post_compile=False, expanding=False, escaped_from=None, **kw ): if self.positional: if positional_names is not None: positional_names.append(name) else: self.positiontup.append(name) self.positiontup_level[name] = len(self.stack) if not escaped_from: if _BIND_TRANSLATE_RE.search(name): # not quite the translate use case as we want to # also get a quick boolean if we even found # unusual characters in the name new_name = _BIND_TRANSLATE_RE.sub( lambda m: _BIND_TRANSLATE_CHARS[m.group(0)], name, ) escaped_from = name name = new_name if escaped_from: if not self.escaped_bind_names: self.escaped_bind_names = {} self.escaped_bind_names[escaped_from] = name if post_compile: return "__[POSTCOMPILE_%s]" % name else: return self.bindtemplate % {"name": name} def visit_cte( self, cte, asfrom=False, ashint=False, fromhints=None, visiting_cte=None, from_linter=None, **kwargs ): self._init_cte_state() kwargs["visiting_cte"] = cte cte_name = cte.name if isinstance(cte_name, elements._truncated_label): cte_name = self._truncated_identifier("alias", cte_name) is_new_cte = True embedded_in_current_named_cte = False _reference_cte = cte._get_reference_cte() if _reference_cte in self.level_name_by_cte: cte_level, _ = self.level_name_by_cte[_reference_cte] assert _ == cte_name else: cte_level = len(self.stack) if cte.nesting else 1 cte_level_name = (cte_level, cte_name) if cte_level_name in self.ctes_by_level_name: existing_cte = self.ctes_by_level_name[cte_level_name] embedded_in_current_named_cte = visiting_cte is existing_cte # we've generated a same-named CTE that we are enclosed in, # or this is the same CTE. just return the name. if cte is existing_cte._restates or cte is existing_cte: is_new_cte = False elif existing_cte is cte._restates: # we've generated a same-named CTE that is # enclosed in us - we take precedence, so # discard the text for the "inner". del self.ctes[existing_cte] existing_cte_reference_cte = existing_cte._get_reference_cte() # TODO: determine if these assertions are correct. they # pass for current test cases # assert existing_cte_reference_cte is _reference_cte # assert existing_cte_reference_cte is existing_cte del self.level_name_by_cte[existing_cte_reference_cte] else: # if the two CTEs are deep-copy identical, consider them # the same, **if** they are clones, that is, they came from # the ORM or other visit method if ( cte._is_clone_of is not None or existing_cte._is_clone_of is not None ) and cte.compare(existing_cte): is_new_cte = False else: raise exc.CompileError( "Multiple, unrelated CTEs found with " "the same name: %r" % cte_name ) if not asfrom and not is_new_cte: return None if cte._cte_alias is not None: pre_alias_cte = cte._cte_alias cte_pre_alias_name = cte._cte_alias.name if isinstance(cte_pre_alias_name, elements._truncated_label): cte_pre_alias_name = self._truncated_identifier( "alias", cte_pre_alias_name ) else: pre_alias_cte = cte cte_pre_alias_name = None if is_new_cte: self.ctes_by_level_name[cte_level_name] = cte self.level_name_by_cte[_reference_cte] = cte_level_name if ( "autocommit" in cte.element._execution_options and "autocommit" not in self.execution_options ): self.execution_options = self.execution_options.union( { "autocommit": cte.element._execution_options[ "autocommit" ] } ) if self.positional: self.cte_level[cte] = cte_level if pre_alias_cte not in self.ctes: self.visit_cte(pre_alias_cte, **kwargs) if not cte_pre_alias_name and cte not in self.ctes: if cte.recursive: self.ctes_recursive = True text = self.preparer.format_alias(cte, cte_name) if cte.recursive: if isinstance(cte.element, selectable.Select): col_source = cte.element elif isinstance(cte.element, selectable.CompoundSelect): col_source = cte.element.selects[0] else: assert False, "cte should only be against SelectBase" # TODO: can we get at the .columns_plus_names collection # that is already (or will be?) generated for the SELECT # rather than calling twice? recur_cols = [ # TODO: proxy_name is not technically safe, # see test_cte-> # test_with_recursive_no_name_currently_buggy. not # clear what should be done with such a case fallback_label_name or proxy_name for ( _, proxy_name, fallback_label_name, c, repeated, ) in (col_source._generate_columns_plus_names(True)) if not repeated ] text += "(%s)" % ( ", ".join( self.preparer.format_label_name( ident, anon_map=self.anon_map ) for ident in recur_cols ) ) if self.positional: kwargs["positional_names"] = self.cte_positional[cte] = [] assert kwargs.get("subquery", False) is False if not self.stack: # toplevel, this is a stringify of the # cte directly. just compile the inner # the way alias() does. return cte.element._compiler_dispatch( self, asfrom=asfrom, **kwargs ) else: prefixes = self._generate_prefixes( cte, cte._prefixes, **kwargs ) inner = cte.element._compiler_dispatch( self, asfrom=True, **kwargs ) text += " AS %s\n(%s)" % (prefixes, inner) if cte._suffixes: text += " " + self._generate_prefixes( cte, cte._suffixes, **kwargs ) self.ctes[cte] = text if asfrom: if from_linter: from_linter.froms[cte] = cte_name if not is_new_cte and embedded_in_current_named_cte: return self.preparer.format_alias(cte, cte_name) if cte_pre_alias_name: text = self.preparer.format_alias(cte, cte_pre_alias_name) if self.preparer._requires_quotes(cte_name): cte_name = self.preparer.quote(cte_name) text += self.get_render_as_alias_suffix(cte_name) return text else: return self.preparer.format_alias(cte, cte_name) def visit_table_valued_alias(self, element, **kw): if element.joins_implicitly: kw["from_linter"] = None if element._is_lateral: return self.visit_lateral(element, **kw) else: return self.visit_alias(element, **kw) def visit_table_valued_column(self, element, **kw): return self.visit_column(element, **kw) def visit_alias( self, alias, asfrom=False, ashint=False, iscrud=False, fromhints=None, subquery=False, lateral=False, enclosing_alias=None, from_linter=None, **kwargs ): if lateral: if "enclosing_lateral" not in kwargs: # if lateral is set and enclosing_lateral is not # present, we assume we are being called directly # from visit_lateral() and we need to set enclosing_lateral. assert alias._is_lateral kwargs["enclosing_lateral"] = alias # for lateral objects, we track a second from_linter that is... # lateral! to the level above us. if ( from_linter and "lateral_from_linter" not in kwargs and "enclosing_lateral" in kwargs ): kwargs["lateral_from_linter"] = from_linter if enclosing_alias is not None and enclosing_alias.element is alias: inner = alias.element._compiler_dispatch( self, asfrom=asfrom, ashint=ashint, iscrud=iscrud, fromhints=fromhints, lateral=lateral, enclosing_alias=alias, **kwargs ) if subquery and (asfrom or lateral): inner = "(%s)" % (inner,) return inner else: enclosing_alias = kwargs["enclosing_alias"] = alias if asfrom or ashint: if isinstance(alias.name, elements._truncated_label): alias_name = self._truncated_identifier("alias", alias.name) else: alias_name = alias.name if ashint: return self.preparer.format_alias(alias, alias_name) elif asfrom: if from_linter: from_linter.froms[alias] = alias_name inner = alias.element._compiler_dispatch( self, asfrom=True, lateral=lateral, **kwargs ) if subquery: inner = "(%s)" % (inner,) ret = inner + self.get_render_as_alias_suffix( self.preparer.format_alias(alias, alias_name) ) if alias._supports_derived_columns and alias._render_derived: ret += "(%s)" % ( ", ".join( "%s%s" % ( self.preparer.quote(col.name), " %s" % self.dialect.type_compiler.process( col.type, **kwargs ) if alias._render_derived_w_types else "", ) for col in alias.c ) ) if fromhints and alias in fromhints: ret = self.format_from_hint_text( ret, alias, fromhints[alias], iscrud ) return ret else: # note we cancel the "subquery" flag here as well return alias.element._compiler_dispatch( self, lateral=lateral, **kwargs ) def visit_subquery(self, subquery, **kw): kw["subquery"] = True return self.visit_alias(subquery, **kw) def visit_lateral(self, lateral_, **kw): kw["lateral"] = True return "LATERAL %s" % self.visit_alias(lateral_, **kw) def visit_tablesample(self, tablesample, asfrom=False, **kw): text = "%s TABLESAMPLE %s" % ( self.visit_alias(tablesample, asfrom=True, **kw), tablesample._get_method()._compiler_dispatch(self, **kw), ) if tablesample.seed is not None: text += " REPEATABLE (%s)" % ( tablesample.seed._compiler_dispatch(self, **kw) ) return text def visit_values(self, element, asfrom=False, from_linter=None, **kw): kw.setdefault("literal_binds", element.literal_binds) v = "VALUES %s" % ", ".join( self.process( elements.Tuple( types=element._column_types, *elem ).self_group(), **kw ) for chunk in element._data for elem in chunk ) if isinstance(element.name, elements._truncated_label): name = self._truncated_identifier("values", element.name) else: name = element.name if element._is_lateral: lateral = "LATERAL " else: lateral = "" if asfrom: if from_linter: from_linter.froms[element] = ( name if name is not None else "(unnamed VALUES element)" ) if name: v = "%s(%s)%s (%s)" % ( lateral, v, self.get_render_as_alias_suffix(self.preparer.quote(name)), ( ", ".join( c._compiler_dispatch( self, include_table=False, **kw ) for c in element.columns ) ), ) else: v = "%s(%s)" % (lateral, v) return v def get_render_as_alias_suffix(self, alias_name_text): return " AS " + alias_name_text def _add_to_result_map(self, keyname, name, objects, type_): if keyname is None or keyname == "*": self._ordered_columns = False self._ad_hoc_textual = True if type_._is_tuple_type: raise exc.CompileError( "Most backends don't support SELECTing " "from a tuple() object. If this is an ORM query, " "consider using the Bundle object." ) self._result_columns.append((keyname, name, objects, type_)) def _label_returning_column( self, stmt, column, column_clause_args=None, **kw ): """Render a column with necessary labels inside of a RETURNING clause. This method is provided for individual dialects in place of calling the _label_select_column method directly, so that the two use cases of RETURNING vs. SELECT can be disambiguated going forward. .. versionadded:: 1.4.21 """ return self._label_select_column( None, column, True, False, {} if column_clause_args is None else column_clause_args, **kw ) def _label_select_column( self, select, column, populate_result_map, asfrom, column_clause_args, name=None, proxy_name=None, fallback_label_name=None, within_columns_clause=True, column_is_repeated=False, need_column_expressions=False, ): """produce labeled columns present in a select().""" impl = column.type.dialect_impl(self.dialect) if impl._has_column_expression and ( need_column_expressions or populate_result_map ): col_expr = impl.column_expression(column) else: col_expr = column if populate_result_map: # pass an "add_to_result_map" callable into the compilation # of embedded columns. this collects information about the # column as it will be fetched in the result and is coordinated # with cursor.description when the query is executed. add_to_result_map = self._add_to_result_map # if the SELECT statement told us this column is a repeat, # wrap the callable with one that prevents the addition of the # targets if column_is_repeated: _add_to_result_map = add_to_result_map def add_to_result_map(keyname, name, objects, type_): _add_to_result_map(keyname, name, (), type_) # if we redefined col_expr for type expressions, wrap the # callable with one that adds the original column to the targets elif col_expr is not column: _add_to_result_map = add_to_result_map def add_to_result_map(keyname, name, objects, type_): _add_to_result_map( keyname, name, (column,) + objects, type_ ) else: add_to_result_map = None # this method is used by some of the dialects for RETURNING, # which has different inputs. _label_returning_column was added # as the better target for this now however for 1.4 we will keep # _label_select_column directly compatible with this use case. # these assertions right now set up the current expected inputs assert within_columns_clause, ( "_label_select_column is only relevant within " "the columns clause of a SELECT or RETURNING" ) if isinstance(column, elements.Label): if col_expr is not column: result_expr = _CompileLabel( col_expr, column.name, alt_names=(column.element,) ) else: result_expr = col_expr elif name: # here, _columns_plus_names has determined there's an explicit # label name we need to use. this is the default for # tablenames_plus_columnnames as well as when columns are being # deduplicated on name assert ( proxy_name is not None ), "proxy_name is required if 'name' is passed" result_expr = _CompileLabel( col_expr, name, alt_names=( proxy_name, # this is a hack to allow legacy result column lookups # to work as they did before; this goes away in 2.0. # TODO: this only seems to be tested indirectly # via test/orm/test_deprecations.py. should be a # resultset test for this column._tq_label, ), ) else: # determine here whether this column should be rendered in # a labelled context or not, as we were given no required label # name from the caller. Here we apply heuristics based on the kind # of SQL expression involved. if col_expr is not column: # type-specific expression wrapping the given column, # so we render a label render_with_label = True elif isinstance(column, elements.ColumnClause): # table-bound column, we render its name as a label if we are # inside of a subquery only render_with_label = ( asfrom and not column.is_literal and column.table is not None ) elif isinstance(column, elements.TextClause): render_with_label = False elif isinstance(column, elements.UnaryExpression): render_with_label = column.wraps_column_expression or asfrom elif ( # general class of expressions that don't have a SQL-column # addressible name. includes scalar selects, bind parameters, # SQL functions, others not isinstance(column, elements.NamedColumn) # deeper check that indicates there's no natural "name" to # this element, which accommodates for custom SQL constructs # that might have a ".name" attribute (but aren't SQL # functions) but are not implementing this more recently added # base class. in theory the "NamedColumn" check should be # enough, however here we seek to maintain legacy behaviors # as well. and column._non_anon_label is None ): render_with_label = True else: render_with_label = False if render_with_label: if not fallback_label_name: # used by the RETURNING case right now. we generate it # here as 3rd party dialects may be referring to # _label_select_column method directly instead of the # just-added _label_returning_column method assert not column_is_repeated fallback_label_name = column._anon_name_label fallback_label_name = ( elements._truncated_label(fallback_label_name) if not isinstance( fallback_label_name, elements._truncated_label ) else fallback_label_name ) result_expr = _CompileLabel( col_expr, fallback_label_name, alt_names=(proxy_name,) ) else: result_expr = col_expr column_clause_args.update( within_columns_clause=within_columns_clause, add_to_result_map=add_to_result_map, ) return result_expr._compiler_dispatch(self, **column_clause_args) def format_from_hint_text(self, sqltext, table, hint, iscrud): hinttext = self.get_from_hint_text(table, hint) if hinttext: sqltext += " " + hinttext return sqltext def get_select_hint_text(self, byfroms): return None def get_from_hint_text(self, table, text): return None def get_crud_hint_text(self, table, text): return None def get_statement_hint_text(self, hint_texts): return " ".join(hint_texts) _default_stack_entry = util.immutabledict( [("correlate_froms", frozenset()), ("asfrom_froms", frozenset())] ) def _display_froms_for_select( self, select_stmt, asfrom, lateral=False, **kw ): # utility method to help external dialects # get the correct from list for a select. # specifically the oracle dialect needs this feature # right now. toplevel = not self.stack entry = self._default_stack_entry if toplevel else self.stack[-1] compile_state = select_stmt._compile_state_factory(select_stmt, self) correlate_froms = entry["correlate_froms"] asfrom_froms = entry["asfrom_froms"] if asfrom and not lateral: froms = compile_state._get_display_froms( explicit_correlate_froms=correlate_froms.difference( asfrom_froms ), implicit_correlate_froms=(), ) else: froms = compile_state._get_display_froms( explicit_correlate_froms=correlate_froms, implicit_correlate_froms=asfrom_froms, ) return froms translate_select_structure = None """if not ``None``, should be a callable which accepts ``(select_stmt, **kw)`` and returns a select object. this is used for structural changes mostly to accommodate for LIMIT/OFFSET schemes """ def visit_select( self, select_stmt, asfrom=False, insert_into=False, fromhints=None, compound_index=None, select_wraps_for=None, lateral=False, from_linter=None, **kwargs ): assert select_wraps_for is None, ( "SQLAlchemy 1.4 requires use of " "the translate_select_structure hook for structural " "translations of SELECT objects" ) # initial setup of SELECT. the compile_state_factory may now # be creating a totally different SELECT from the one that was # passed in. for ORM use this will convert from an ORM-state # SELECT to a regular "Core" SELECT. other composed operations # such as computation of joins will be performed. kwargs["within_columns_clause"] = False compile_state = select_stmt._compile_state_factory( select_stmt, self, **kwargs ) select_stmt = compile_state.statement toplevel = not self.stack if toplevel and not self.compile_state: self.compile_state = compile_state is_embedded_select = compound_index is not None or insert_into # translate step for Oracle, SQL Server which often need to # restructure the SELECT to allow for LIMIT/OFFSET and possibly # other conditions if self.translate_select_structure: new_select_stmt = self.translate_select_structure( select_stmt, asfrom=asfrom, **kwargs ) # if SELECT was restructured, maintain a link to the originals # and assemble a new compile state if new_select_stmt is not select_stmt: compile_state_wraps_for = compile_state select_wraps_for = select_stmt select_stmt = new_select_stmt compile_state = select_stmt._compile_state_factory( select_stmt, self, **kwargs ) select_stmt = compile_state.statement entry = self._default_stack_entry if toplevel else self.stack[-1] populate_result_map = need_column_expressions = ( toplevel or entry.get("need_result_map_for_compound", False) or entry.get("need_result_map_for_nested", False) ) # indicates there is a CompoundSelect in play and we are not the # first select if compound_index: populate_result_map = False # this was first proposed as part of #3372; however, it is not # reached in current tests and could possibly be an assertion # instead. if not populate_result_map and "add_to_result_map" in kwargs: del kwargs["add_to_result_map"] froms = self._setup_select_stack( select_stmt, compile_state, entry, asfrom, lateral, compound_index ) column_clause_args = kwargs.copy() column_clause_args.update( {"within_label_clause": False, "within_columns_clause": False} ) text = "SELECT " # we're off to a good start ! if select_stmt._hints: hint_text, byfrom = self._setup_select_hints(select_stmt) if hint_text: text += hint_text + " " else: byfrom = None if select_stmt._independent_ctes: for cte in select_stmt._independent_ctes: cte._compiler_dispatch(self, **kwargs) if select_stmt._prefixes: text += self._generate_prefixes( select_stmt, select_stmt._prefixes, **kwargs ) text += self.get_select_precolumns(select_stmt, **kwargs) # the actual list of columns to print in the SELECT column list. inner_columns = [ c for c in [ self._label_select_column( select_stmt, column, populate_result_map, asfrom, column_clause_args, name=name, proxy_name=proxy_name, fallback_label_name=fallback_label_name, column_is_repeated=repeated, need_column_expressions=need_column_expressions, ) for ( name, proxy_name, fallback_label_name, column, repeated, ) in compile_state.columns_plus_names ] if c is not None ] if populate_result_map and select_wraps_for is not None: # if this select was generated from translate_select, # rewrite the targeted columns in the result map translate = dict( zip( [ name for ( key, proxy_name, fallback_label_name, name, repeated, ) in compile_state.columns_plus_names ], [ name for ( key, proxy_name, fallback_label_name, name, repeated, ) in compile_state_wraps_for.columns_plus_names ], ) ) self._result_columns = [ (key, name, tuple(translate.get(o, o) for o in obj), type_) for key, name, obj, type_ in self._result_columns ] text = self._compose_select_body( text, select_stmt, compile_state, inner_columns, froms, byfrom, toplevel, kwargs, ) if select_stmt._statement_hints: per_dialect = [ ht for (dialect_name, ht) in select_stmt._statement_hints if dialect_name in ("*", self.dialect.name) ] if per_dialect: text += " " + self.get_statement_hint_text(per_dialect) # In compound query, CTEs are shared at the compound level if self.ctes and (not is_embedded_select or toplevel): nesting_level = len(self.stack) if not toplevel else None text = ( self._render_cte_clause( nesting_level=nesting_level, visiting_cte=kwargs.get("visiting_cte"), ) + text ) if select_stmt._suffixes: text += " " + self._generate_prefixes( select_stmt, select_stmt._suffixes, **kwargs ) self.stack.pop(-1) return text def _setup_select_hints(self, select): byfrom = dict( [ ( from_, hinttext % {"name": from_._compiler_dispatch(self, ashint=True)}, ) for (from_, dialect), hinttext in select._hints.items() if dialect in ("*", self.dialect.name) ] ) hint_text = self.get_select_hint_text(byfrom) return hint_text, byfrom def _setup_select_stack( self, select, compile_state, entry, asfrom, lateral, compound_index ): correlate_froms = entry["correlate_froms"] asfrom_froms = entry["asfrom_froms"] if compound_index == 0: entry["select_0"] = select elif compound_index: select_0 = entry["select_0"] numcols = len(select_0._all_selected_columns) if len(compile_state.columns_plus_names) != numcols: raise exc.CompileError( "All selectables passed to " "CompoundSelect must have identical numbers of " "columns; select #%d has %d columns, select " "#%d has %d" % ( 1, numcols, compound_index + 1, len(select._all_selected_columns), ) ) if asfrom and not lateral: froms = compile_state._get_display_froms( explicit_correlate_froms=correlate_froms.difference( asfrom_froms ), implicit_correlate_froms=(), ) else: froms = compile_state._get_display_froms( explicit_correlate_froms=correlate_froms, implicit_correlate_froms=asfrom_froms, ) new_correlate_froms = set(selectable._from_objects(*froms)) all_correlate_froms = new_correlate_froms.union(correlate_froms) new_entry = { "asfrom_froms": new_correlate_froms, "correlate_froms": all_correlate_froms, "selectable": select, "compile_state": compile_state, } self.stack.append(new_entry) return froms def _compose_select_body( self, text, select, compile_state, inner_columns, froms, byfrom, toplevel, kwargs, ): text += ", ".join(inner_columns) if self.linting & COLLECT_CARTESIAN_PRODUCTS: from_linter = FromLinter({}, set()) warn_linting = self.linting & WARN_LINTING if toplevel: self.from_linter = from_linter else: from_linter = None warn_linting = False if froms: text += " \nFROM " if select._hints: text += ", ".join( [ f._compiler_dispatch( self, asfrom=True, fromhints=byfrom, from_linter=from_linter, **kwargs ) for f in froms ] ) else: text += ", ".join( [ f._compiler_dispatch( self, asfrom=True, from_linter=from_linter, **kwargs ) for f in froms ] ) else: text += self.default_from() if select._where_criteria: t = self._generate_delimited_and_list( select._where_criteria, from_linter=from_linter, **kwargs ) if t: text += " \nWHERE " + t if warn_linting: from_linter.warn() if select._group_by_clauses: text += self.group_by_clause(select, **kwargs) if select._having_criteria: t = self._generate_delimited_and_list( select._having_criteria, **kwargs ) if t: text += " \nHAVING " + t if select._order_by_clauses: text += self.order_by_clause(select, **kwargs) if select._has_row_limiting_clause: text += self._row_limit_clause(select, **kwargs) if select._for_update_arg is not None: text += self.for_update_clause(select, **kwargs) return text def _generate_prefixes(self, stmt, prefixes, **kw): clause = " ".join( prefix._compiler_dispatch(self, **kw) for prefix, dialect_name in prefixes if dialect_name is None or dialect_name == self.dialect.name ) if clause: clause += " " return clause def _render_cte_clause( self, nesting_level=None, include_following_stack=False, visiting_cte=None, ): """ include_following_stack Also render the nesting CTEs on the next stack. Useful for SQL structures like UNION or INSERT that can wrap SELECT statements containing nesting CTEs. """ if not self.ctes: return "" if nesting_level and nesting_level > 1: ctes = util.OrderedDict() for cte in list(self.ctes.keys()): cte_level, cte_name = self.level_name_by_cte[ cte._get_reference_cte() ] is_rendered_level = cte_level == nesting_level or ( include_following_stack and cte_level == nesting_level + 1 ) if not (cte.nesting and is_rendered_level): continue ctes[cte] = self.ctes[cte] else: ctes = self.ctes if not ctes: return "" ctes_recursive = any([cte.recursive for cte in ctes]) if self.positional: self.cte_order[visiting_cte].extend(ctes) if visiting_cte is None and self.cte_order: assert self.positiontup is not None def get_nested_positional(cte): if cte in self.cte_order: children = self.cte_order.pop(cte) to_add = list( itertools.chain.from_iterable( get_nested_positional(child_cte) for child_cte in children ) ) if cte in self.cte_positional: return reorder_positional( self.cte_positional[cte], to_add, self.cte_level[children[0]], ) else: return to_add else: return self.cte_positional.get(cte, []) def reorder_positional(pos, to_add, level): if not level: return to_add + pos index = 0 for index, name in enumerate(reversed(pos)): if self.positiontup_level[name] < level: # type: ignore[index] # noqa: E501 break return pos[:-index] + to_add + pos[-index:] to_add = get_nested_positional(None) self.positiontup = reorder_positional( self.positiontup, to_add, nesting_level ) cte_text = self.get_cte_preamble(ctes_recursive) + " " cte_text += ", \n".join([txt for txt in ctes.values()]) cte_text += "\n " if nesting_level and nesting_level > 1: for cte in list(ctes.keys()): cte_level, cte_name = self.level_name_by_cte[ cte._get_reference_cte() ] del self.ctes[cte] del self.ctes_by_level_name[(cte_level, cte_name)] del self.level_name_by_cte[cte._get_reference_cte()] return cte_text def get_cte_preamble(self, recursive): if recursive: return "WITH RECURSIVE" else: return "WITH" def get_select_precolumns(self, select, **kw): """Called when building a ``SELECT`` statement, position is just before column list. """ if select._distinct_on: util.warn_deprecated( "DISTINCT ON is currently supported only by the PostgreSQL " "dialect. Use of DISTINCT ON for other backends is currently " "silently ignored, however this usage is deprecated, and will " "raise CompileError in a future release for all backends " "that do not support this syntax.", version="1.4", ) return "DISTINCT " if select._distinct else "" def group_by_clause(self, select, **kw): """allow dialects to customize how GROUP BY is rendered.""" group_by = self._generate_delimited_list( select._group_by_clauses, OPERATORS[operators.comma_op], **kw ) if group_by: return " GROUP BY " + group_by else: return "" def order_by_clause(self, select, **kw): """allow dialects to customize how ORDER BY is rendered.""" order_by = self._generate_delimited_list( select._order_by_clauses, OPERATORS[operators.comma_op], **kw ) if order_by: return " ORDER BY " + order_by else: return "" def for_update_clause(self, select, **kw): return " FOR UPDATE" def returning_clause(self, stmt, returning_cols): raise exc.CompileError( "RETURNING is not supported by this " "dialect's statement compiler." ) def limit_clause(self, select, **kw): text = "" if select._limit_clause is not None: text += "\n LIMIT " + self.process(select._limit_clause, **kw) if select._offset_clause is not None: if select._limit_clause is None: text += "\n LIMIT -1" text += " OFFSET " + self.process(select._offset_clause, **kw) return text def fetch_clause(self, select, **kw): text = "" if select._offset_clause is not None: text += "\n OFFSET %s ROWS" % self.process( select._offset_clause, **kw ) if select._fetch_clause is not None: text += "\n FETCH FIRST %s%s ROWS %s" % ( self.process(select._fetch_clause, **kw), " PERCENT" if select._fetch_clause_options["percent"] else "", "WITH TIES" if select._fetch_clause_options["with_ties"] else "ONLY", ) return text def visit_table( self, table, asfrom=False, iscrud=False, ashint=False, fromhints=None, use_schema=True, from_linter=None, **kwargs ): if from_linter: from_linter.froms[table] = table.fullname if asfrom or ashint: effective_schema = self.preparer.schema_for_object(table) if use_schema and effective_schema: ret = ( self.preparer.quote_schema(effective_schema) + "." + self.preparer.quote(table.name) ) else: ret = self.preparer.quote(table.name) if fromhints and table in fromhints: ret = self.format_from_hint_text( ret, table, fromhints[table], iscrud ) return ret else: return "" def visit_join(self, join, asfrom=False, from_linter=None, **kwargs): if from_linter: from_linter.edges.update( itertools.product( join.left._from_objects, join.right._from_objects ) ) if join.full: join_type = " FULL OUTER JOIN " elif join.isouter: join_type = " LEFT OUTER JOIN " else: join_type = " JOIN " return ( join.left._compiler_dispatch( self, asfrom=True, from_linter=from_linter, **kwargs ) + join_type + join.right._compiler_dispatch( self, asfrom=True, from_linter=from_linter, **kwargs ) + " ON " # TODO: likely need asfrom=True here? + join.onclause._compiler_dispatch( self, from_linter=from_linter, **kwargs ) ) def _setup_crud_hints(self, stmt, table_text): dialect_hints = dict( [ (table, hint_text) for (table, dialect), hint_text in stmt._hints.items() if dialect in ("*", self.dialect.name) ] ) if stmt.table in dialect_hints: table_text = self.format_from_hint_text( table_text, stmt.table, dialect_hints[stmt.table], True ) return dialect_hints, table_text def visit_insert(self, insert_stmt, **kw): compile_state = insert_stmt._compile_state_factory( insert_stmt, self, **kw ) insert_stmt = compile_state.statement toplevel = not self.stack if toplevel: self.isinsert = True if not self.dml_compile_state: self.dml_compile_state = compile_state if not self.compile_state: self.compile_state = compile_state self.stack.append( { "correlate_froms": set(), "asfrom_froms": set(), "selectable": insert_stmt, } ) crud_params = crud._get_crud_params( self, insert_stmt, compile_state, **kw ) if ( not crud_params and not self.dialect.supports_default_values and not self.dialect.supports_default_metavalue and not self.dialect.supports_empty_insert ): raise exc.CompileError( "The '%s' dialect with current database " "version settings does not support empty " "inserts." % self.dialect.name ) if compile_state._has_multi_parameters: if not self.dialect.supports_multivalues_insert: raise exc.CompileError( "The '%s' dialect with current database " "version settings does not support " "in-place multirow inserts." % self.dialect.name ) crud_params_single = crud_params[0] else: crud_params_single = crud_params preparer = self.preparer supports_default_values = self.dialect.supports_default_values text = "INSERT " if insert_stmt._prefixes: text += self._generate_prefixes( insert_stmt, insert_stmt._prefixes, **kw ) text += "INTO " table_text = preparer.format_table(insert_stmt.table) if insert_stmt._hints: _, table_text = self._setup_crud_hints(insert_stmt, table_text) if insert_stmt._independent_ctes: for cte in insert_stmt._independent_ctes: cte._compiler_dispatch(self, **kw) text += table_text if crud_params_single or not supports_default_values: text += " (%s)" % ", ".join( [expr for c, expr, value in crud_params_single] ) if self.returning or insert_stmt._returning: returning_clause = self.returning_clause( insert_stmt, self.returning or insert_stmt._returning ) if self.returning_precedes_values: text += " " + returning_clause else: returning_clause = None if insert_stmt.select is not None: # placed here by crud.py select_text = self.process( self.stack[-1]["insert_from_select"], insert_into=True, **kw ) if self.ctes and self.dialect.cte_follows_insert: nesting_level = len(self.stack) if not toplevel else None text += " %s%s" % ( self._render_cte_clause( nesting_level=nesting_level, include_following_stack=True, visiting_cte=kw.get("visiting_cte"), ), select_text, ) else: text += " %s" % select_text elif not crud_params and supports_default_values: text += " DEFAULT VALUES" elif compile_state._has_multi_parameters: text += " VALUES %s" % ( ", ".join( "(%s)" % (", ".join(value for c, expr, value in crud_param_set)) for crud_param_set in crud_params ) ) else: insert_single_values_expr = ", ".join( [value for c, expr, value in crud_params] ) text += " VALUES (%s)" % insert_single_values_expr if toplevel: self.insert_single_values_expr = insert_single_values_expr if insert_stmt._post_values_clause is not None: post_values_clause = self.process( insert_stmt._post_values_clause, **kw ) if post_values_clause: text += " " + post_values_clause if returning_clause and not self.returning_precedes_values: text += " " + returning_clause if self.ctes and not self.dialect.cte_follows_insert: nesting_level = len(self.stack) if not toplevel else None text = ( self._render_cte_clause( nesting_level=nesting_level, include_following_stack=True, visiting_cte=kw.get("visiting_cte"), ) + text ) self.stack.pop(-1) return text def update_limit_clause(self, update_stmt): """Provide a hook for MySQL to add LIMIT to the UPDATE""" return None def update_tables_clause(self, update_stmt, from_table, extra_froms, **kw): """Provide a hook to override the initial table clause in an UPDATE statement. MySQL overrides this. """ kw["asfrom"] = True return from_table._compiler_dispatch(self, iscrud=True, **kw) def update_from_clause( self, update_stmt, from_table, extra_froms, from_hints, **kw ): """Provide a hook to override the generation of an UPDATE..FROM clause. MySQL and MSSQL override this. """ raise NotImplementedError( "This backend does not support multiple-table " "criteria within UPDATE" ) def visit_update(self, update_stmt, **kw): compile_state = update_stmt._compile_state_factory( update_stmt, self, **kw ) update_stmt = compile_state.statement toplevel = not self.stack if toplevel: self.isupdate = True if not self.dml_compile_state: self.dml_compile_state = compile_state if not self.compile_state: self.compile_state = compile_state extra_froms = compile_state._extra_froms is_multitable = bool(extra_froms) if is_multitable: # main table might be a JOIN main_froms = set(selectable._from_objects(update_stmt.table)) render_extra_froms = [ f for f in extra_froms if f not in main_froms ] correlate_froms = main_froms.union(extra_froms) else: render_extra_froms = [] correlate_froms = {update_stmt.table} self.stack.append( { "correlate_froms": correlate_froms, "asfrom_froms": correlate_froms, "selectable": update_stmt, } ) text = "UPDATE " if update_stmt._prefixes: text += self._generate_prefixes( update_stmt, update_stmt._prefixes, **kw ) table_text = self.update_tables_clause( update_stmt, update_stmt.table, render_extra_froms, **kw ) crud_params = crud._get_crud_params( self, update_stmt, compile_state, **kw ) if update_stmt._hints: dialect_hints, table_text = self._setup_crud_hints( update_stmt, table_text ) else: dialect_hints = None if update_stmt._independent_ctes: for cte in update_stmt._independent_ctes: cte._compiler_dispatch(self, **kw) text += table_text text += " SET " text += ", ".join(expr + "=" + value for c, expr, value in crud_params) if self.returning or update_stmt._returning: if self.returning_precedes_values: text += " " + self.returning_clause( update_stmt, self.returning or update_stmt._returning ) if extra_froms: extra_from_text = self.update_from_clause( update_stmt, update_stmt.table, render_extra_froms, dialect_hints, **kw ) if extra_from_text: text += " " + extra_from_text if update_stmt._where_criteria: t = self._generate_delimited_and_list( update_stmt._where_criteria, **kw ) if t: text += " WHERE " + t limit_clause = self.update_limit_clause(update_stmt) if limit_clause: text += " " + limit_clause if ( self.returning or update_stmt._returning ) and not self.returning_precedes_values: text += " " + self.returning_clause( update_stmt, self.returning or update_stmt._returning ) if self.ctes: nesting_level = len(self.stack) if not toplevel else None text = ( self._render_cte_clause( nesting_level=nesting_level, visiting_cte=kw.get("visiting_cte"), ) + text ) self.stack.pop(-1) return text def delete_extra_from_clause( self, update_stmt, from_table, extra_froms, from_hints, **kw ): """Provide a hook to override the generation of an DELETE..FROM clause. This can be used to implement DELETE..USING for example. MySQL and MSSQL override this. """ raise NotImplementedError( "This backend does not support multiple-table " "criteria within DELETE" ) def delete_table_clause(self, delete_stmt, from_table, extra_froms): return from_table._compiler_dispatch(self, asfrom=True, iscrud=True) def visit_delete(self, delete_stmt, **kw): compile_state = delete_stmt._compile_state_factory( delete_stmt, self, **kw ) delete_stmt = compile_state.statement toplevel = not self.stack if toplevel: self.isdelete = True if not self.dml_compile_state: self.dml_compile_state = compile_state if not self.compile_state: self.compile_state = compile_state extra_froms = compile_state._extra_froms correlate_froms = {delete_stmt.table}.union(extra_froms) self.stack.append( { "correlate_froms": correlate_froms, "asfrom_froms": correlate_froms, "selectable": delete_stmt, } ) text = "DELETE " if delete_stmt._prefixes: text += self._generate_prefixes( delete_stmt, delete_stmt._prefixes, **kw ) text += "FROM " table_text = self.delete_table_clause( delete_stmt, delete_stmt.table, extra_froms ) if delete_stmt._hints: dialect_hints, table_text = self._setup_crud_hints( delete_stmt, table_text ) else: dialect_hints = None if delete_stmt._independent_ctes: for cte in delete_stmt._independent_ctes: cte._compiler_dispatch(self, **kw) text += table_text if delete_stmt._returning: if self.returning_precedes_values: text += " " + self.returning_clause( delete_stmt, delete_stmt._returning ) if extra_froms: extra_from_text = self.delete_extra_from_clause( delete_stmt, delete_stmt.table, extra_froms, dialect_hints, **kw ) if extra_from_text: text += " " + extra_from_text if delete_stmt._where_criteria: t = self._generate_delimited_and_list( delete_stmt._where_criteria, **kw ) if t: text += " WHERE " + t if delete_stmt._returning and not self.returning_precedes_values: text += " " + self.returning_clause( delete_stmt, delete_stmt._returning ) if self.ctes: nesting_level = len(self.stack) if not toplevel else None text = ( self._render_cte_clause( nesting_level=nesting_level, visiting_cte=kw.get("visiting_cte"), ) + text ) self.stack.pop(-1) return text def visit_savepoint(self, savepoint_stmt): return "SAVEPOINT %s" % self.preparer.format_savepoint(savepoint_stmt) def visit_rollback_to_savepoint(self, savepoint_stmt): return "ROLLBACK TO SAVEPOINT %s" % self.preparer.format_savepoint( savepoint_stmt ) def visit_release_savepoint(self, savepoint_stmt): return "RELEASE SAVEPOINT %s" % self.preparer.format_savepoint( savepoint_stmt ) class StrSQLCompiler(SQLCompiler): """A :class:`.SQLCompiler` subclass which allows a small selection of non-standard SQL features to render into a string value. The :class:`.StrSQLCompiler` is invoked whenever a Core expression element is directly stringified without calling upon the :meth:`_expression.ClauseElement.compile` method. It can render a limited set of non-standard SQL constructs to assist in basic stringification, however for more substantial custom or dialect-specific SQL constructs, it will be necessary to make use of :meth:`_expression.ClauseElement.compile` directly. .. seealso:: :ref:`faq_sql_expression_string` """ def _fallback_column_name(self, column): return "<name unknown>" @util.preload_module("sqlalchemy.engine.url") def visit_unsupported_compilation(self, element, err, **kw): if element.stringify_dialect != "default": url = util.preloaded.engine_url dialect = url.URL.create(element.stringify_dialect).get_dialect()() compiler = dialect.statement_compiler(dialect, None) if not isinstance(compiler, StrSQLCompiler): return compiler.process(element) return super(StrSQLCompiler, self).visit_unsupported_compilation( element, err ) def visit_getitem_binary(self, binary, operator, **kw): return "%s[%s]" % ( self.process(binary.left, **kw), self.process(binary.right, **kw), ) def visit_json_getitem_op_binary(self, binary, operator, **kw): return self.visit_getitem_binary(binary, operator, **kw) def visit_json_path_getitem_op_binary(self, binary, operator, **kw): return self.visit_getitem_binary(binary, operator, **kw) def visit_sequence(self, seq, **kw): return "<next sequence value: %s>" % self.preparer.format_sequence(seq) def returning_clause(self, stmt, returning_cols): columns = [ self._label_select_column( None, c, True, False, {}, fallback_label_name=c._non_anon_label ) for c in base._select_iterables(returning_cols) ] return "RETURNING " + ", ".join(columns) def update_from_clause( self, update_stmt, from_table, extra_froms, from_hints, **kw ): kw["asfrom"] = True return "FROM " + ", ".join( t._compiler_dispatch(self, fromhints=from_hints, **kw) for t in extra_froms ) def delete_extra_from_clause( self, update_stmt, from_table, extra_froms, from_hints, **kw ): kw["asfrom"] = True return ", " + ", ".join( t._compiler_dispatch(self, fromhints=from_hints, **kw) for t in extra_froms ) def visit_empty_set_expr(self, type_): return "SELECT 1 WHERE 1!=1" def get_from_hint_text(self, table, text): return "[%s]" % text def visit_regexp_match_op_binary(self, binary, operator, **kw): return self._generate_generic_binary(binary, " <regexp> ", **kw) def visit_not_regexp_match_op_binary(self, binary, operator, **kw): return self._generate_generic_binary(binary, " <not regexp> ", **kw) def visit_regexp_replace_op_binary(self, binary, operator, **kw): return "<regexp replace>(%s, %s)" % ( binary.left._compiler_dispatch(self, **kw), binary.right._compiler_dispatch(self, **kw), ) class DDLCompiler(Compiled): @util.memoized_property def sql_compiler(self): return self.dialect.statement_compiler( self.dialect, None, schema_translate_map=self.schema_translate_map ) @util.memoized_property def type_compiler(self): return self.dialect.type_compiler def construct_params( self, params=None, extracted_parameters=None, escape_names=True ): return None def visit_ddl(self, ddl, **kwargs): # table events can substitute table and schema name context = ddl.context if isinstance(ddl.target, schema.Table): context = context.copy() preparer = self.preparer path = preparer.format_table_seq(ddl.target) if len(path) == 1: table, sch = path[0], "" else: table, sch = path[-1], path[0] context.setdefault("table", table) context.setdefault("schema", sch) context.setdefault("fullname", preparer.format_table(ddl.target)) return self.sql_compiler.post_process_text(ddl.statement % context) def visit_create_schema(self, create, **kw): schema = self.preparer.format_schema(create.element) return "CREATE SCHEMA " + schema def visit_drop_schema(self, drop, **kw): schema = self.preparer.format_schema(drop.element) text = "DROP SCHEMA " + schema if drop.cascade: text += " CASCADE" return text def visit_create_table(self, create, **kw): table = create.element preparer = self.preparer text = "\nCREATE " if table._prefixes: text += " ".join(table._prefixes) + " " text += "TABLE " if create.if_not_exists: text += "IF NOT EXISTS " text += preparer.format_table(table) + " " create_table_suffix = self.create_table_suffix(table) if create_table_suffix: text += create_table_suffix + " " text += "(" separator = "\n" # if only one primary key, specify it along with the column first_pk = False for create_column in create.columns: column = create_column.element try: processed = self.process( create_column, first_pk=column.primary_key and not first_pk ) if processed is not None: text += separator separator = ", \n" text += "\t" + processed if column.primary_key: first_pk = True except exc.CompileError as ce: util.raise_( exc.CompileError( util.u("(in table '%s', column '%s'): %s") % (table.description, column.name, ce.args[0]) ), from_=ce, ) const = self.create_table_constraints( table, _include_foreign_key_constraints=create.include_foreign_key_constraints, # noqa ) if const: text += separator + "\t" + const text += "\n)%s\n\n" % self.post_create_table(table) return text def visit_create_column(self, create, first_pk=False, **kw): column = create.element if column.system: return None text = self.get_column_specification(column, first_pk=first_pk) const = " ".join( self.process(constraint) for constraint in column.constraints ) if const: text += " " + const return text def create_table_constraints( self, table, _include_foreign_key_constraints=None, **kw ): # On some DB order is significant: visit PK first, then the # other constraints (engine.ReflectionTest.testbasic failed on FB2) constraints = [] if table.primary_key: constraints.append(table.primary_key) all_fkcs = table.foreign_key_constraints if _include_foreign_key_constraints is not None: omit_fkcs = all_fkcs.difference(_include_foreign_key_constraints) else: omit_fkcs = set() constraints.extend( [ c for c in table._sorted_constraints if c is not table.primary_key and c not in omit_fkcs ] ) return ", \n\t".join( p for p in ( self.process(constraint) for constraint in constraints if ( constraint._create_rule is None or constraint._create_rule(self) ) and ( not self.dialect.supports_alter or not getattr(constraint, "use_alter", False) ) ) if p is not None ) def visit_drop_table(self, drop, **kw): text = "\nDROP TABLE " if drop.if_exists: text += "IF EXISTS " return text + self.preparer.format_table(drop.element) def visit_drop_view(self, drop, **kw): return "\nDROP VIEW " + self.preparer.format_table(drop.element) def _verify_index_table(self, index): if index.table is None: raise exc.CompileError( "Index '%s' is not associated " "with any table." % index.name ) def visit_create_index( self, create, include_schema=False, include_table_schema=True, **kw ): index = create.element self._verify_index_table(index) preparer = self.preparer text = "CREATE " if index.unique: text += "UNIQUE " if index.name is None: raise exc.CompileError( "CREATE INDEX requires that the index have a name" ) text += "INDEX " if create.if_not_exists: text += "IF NOT EXISTS " text += "%s ON %s (%s)" % ( self._prepared_index_name(index, include_schema=include_schema), preparer.format_table( index.table, use_schema=include_table_schema ), ", ".join( self.sql_compiler.process( expr, include_table=False, literal_binds=True ) for expr in index.expressions ), ) return text def visit_drop_index(self, drop, **kw): index = drop.element if index.name is None: raise exc.CompileError( "DROP INDEX requires that the index have a name" ) text = "\nDROP INDEX " if drop.if_exists: text += "IF EXISTS " return text + self._prepared_index_name(index, include_schema=True) def _prepared_index_name(self, index, include_schema=False): if index.table is not None: effective_schema = self.preparer.schema_for_object(index.table) else: effective_schema = None if include_schema and effective_schema: schema_name = self.preparer.quote_schema(effective_schema) else: schema_name = None index_name = self.preparer.format_index(index) if schema_name: index_name = schema_name + "." + index_name return index_name def visit_add_constraint(self, create, **kw): return "ALTER TABLE %s ADD %s" % ( self.preparer.format_table(create.element.table), self.process(create.element), ) def visit_set_table_comment(self, create, **kw): return "COMMENT ON TABLE %s IS %s" % ( self.preparer.format_table(create.element), self.sql_compiler.render_literal_value( create.element.comment, sqltypes.String() ), ) def visit_drop_table_comment(self, drop, **kw): return "COMMENT ON TABLE %s IS NULL" % self.preparer.format_table( drop.element ) def visit_set_column_comment(self, create, **kw): return "COMMENT ON COLUMN %s IS %s" % ( self.preparer.format_column( create.element, use_table=True, use_schema=True ), self.sql_compiler.render_literal_value( create.element.comment, sqltypes.String() ), ) def visit_drop_column_comment(self, drop, **kw): return "COMMENT ON COLUMN %s IS NULL" % self.preparer.format_column( drop.element, use_table=True ) def get_identity_options(self, identity_options): text = [] if identity_options.increment is not None: text.append("INCREMENT BY %d" % identity_options.increment) if identity_options.start is not None: text.append("START WITH %d" % identity_options.start) if identity_options.minvalue is not None: text.append("MINVALUE %d" % identity_options.minvalue) if identity_options.maxvalue is not None: text.append("MAXVALUE %d" % identity_options.maxvalue) if identity_options.nominvalue is not None: text.append("NO MINVALUE") if identity_options.nomaxvalue is not None: text.append("NO MAXVALUE") if identity_options.cache is not None: text.append("CACHE %d" % identity_options.cache) if identity_options.cycle is not None: text.append("CYCLE" if identity_options.cycle else "NO CYCLE") return " ".join(text) def visit_create_sequence(self, create, prefix=None, **kw): text = "CREATE SEQUENCE %s" % self.preparer.format_sequence( create.element ) if prefix: text += prefix if create.element.start is None: create.element.start = self.dialect.default_sequence_base options = self.get_identity_options(create.element) if options: text += " " + options return text def visit_drop_sequence(self, drop, **kw): return "DROP SEQUENCE %s" % self.preparer.format_sequence(drop.element) def visit_drop_constraint(self, drop, **kw): constraint = drop.element if constraint.name is not None: formatted_name = self.preparer.format_constraint(constraint) else: formatted_name = None if formatted_name is None: raise exc.CompileError( "Can't emit DROP CONSTRAINT for constraint %r; " "it has no name" % drop.element ) return "ALTER TABLE %s DROP CONSTRAINT %s%s" % ( self.preparer.format_table(drop.element.table), formatted_name, drop.cascade and " CASCADE" or "", ) def get_column_specification(self, column, **kwargs): colspec = ( self.preparer.format_column(column) + " " + self.dialect.type_compiler.process( column.type, type_expression=column ) ) default = self.get_column_default_string(column) if default is not None: colspec += " DEFAULT " + default if column.computed is not None: colspec += " " + self.process(column.computed) if ( column.identity is not None and self.dialect.supports_identity_columns ): colspec += " " + self.process(column.identity) if not column.nullable and ( not column.identity or not self.dialect.supports_identity_columns ): colspec += " NOT NULL" return colspec def create_table_suffix(self, table): return "" def post_create_table(self, table): return "" def get_column_default_string(self, column): if isinstance(column.server_default, schema.DefaultClause): if isinstance(column.server_default.arg, util.string_types): return self.sql_compiler.render_literal_value( column.server_default.arg, sqltypes.STRINGTYPE ) else: return self.sql_compiler.process( column.server_default.arg, literal_binds=True ) else: return None def visit_table_or_column_check_constraint(self, constraint, **kw): if constraint.is_column_level: return self.visit_column_check_constraint(constraint) else: return self.visit_check_constraint(constraint) def visit_check_constraint(self, constraint, **kw): text = "" if constraint.name is not None: formatted_name = self.preparer.format_constraint(constraint) if formatted_name is not None: text += "CONSTRAINT %s " % formatted_name text += "CHECK (%s)" % self.sql_compiler.process( constraint.sqltext, include_table=False, literal_binds=True ) text += self.define_constraint_deferrability(constraint) return text def visit_column_check_constraint(self, constraint, **kw): text = "" if constraint.name is not None: formatted_name = self.preparer.format_constraint(constraint) if formatted_name is not None: text += "CONSTRAINT %s " % formatted_name text += "CHECK (%s)" % self.sql_compiler.process( constraint.sqltext, include_table=False, literal_binds=True ) text += self.define_constraint_deferrability(constraint) return text def visit_primary_key_constraint(self, constraint, **kw): if len(constraint) == 0: return "" text = "" if constraint.name is not None: formatted_name = self.preparer.format_constraint(constraint) if formatted_name is not None: text += "CONSTRAINT %s " % formatted_name text += "PRIMARY KEY " text += "(%s)" % ", ".join( self.preparer.quote(c.name) for c in ( constraint.columns_autoinc_first if constraint._implicit_generated else constraint.columns ) ) text += self.define_constraint_deferrability(constraint) return text def visit_foreign_key_constraint(self, constraint, **kw): preparer = self.preparer text = "" if constraint.name is not None: formatted_name = self.preparer.format_constraint(constraint) if formatted_name is not None: text += "CONSTRAINT %s " % formatted_name remote_table = list(constraint.elements)[0].column.table text += "FOREIGN KEY(%s) REFERENCES %s (%s)" % ( ", ".join( preparer.quote(f.parent.name) for f in constraint.elements ), self.define_constraint_remote_table( constraint, remote_table, preparer ), ", ".join( preparer.quote(f.column.name) for f in constraint.elements ), ) text += self.define_constraint_match(constraint) text += self.define_constraint_cascades(constraint) text += self.define_constraint_deferrability(constraint) return text def define_constraint_remote_table(self, constraint, table, preparer): """Format the remote table clause of a CREATE CONSTRAINT clause.""" return preparer.format_table(table) def visit_unique_constraint(self, constraint, **kw): if len(constraint) == 0: return "" text = "" if constraint.name is not None: formatted_name = self.preparer.format_constraint(constraint) if formatted_name is not None: text += "CONSTRAINT %s " % formatted_name text += "UNIQUE (%s)" % ( ", ".join(self.preparer.quote(c.name) for c in constraint) ) text += self.define_constraint_deferrability(constraint) return text def define_constraint_cascades(self, constraint): text = "" if constraint.ondelete is not None: text += " ON DELETE %s" % self.preparer.validate_sql_phrase( constraint.ondelete, FK_ON_DELETE ) if constraint.onupdate is not None: text += " ON UPDATE %s" % self.preparer.validate_sql_phrase( constraint.onupdate, FK_ON_UPDATE ) return text def define_constraint_deferrability(self, constraint): text = "" if constraint.deferrable is not None: if constraint.deferrable: text += " DEFERRABLE" else: text += " NOT DEFERRABLE" if constraint.initially is not None: text += " INITIALLY %s" % self.preparer.validate_sql_phrase( constraint.initially, FK_INITIALLY ) return text def define_constraint_match(self, constraint): text = "" if constraint.match is not None: text += " MATCH %s" % constraint.match return text def visit_computed_column(self, generated, **kw): text = "GENERATED ALWAYS AS (%s)" % self.sql_compiler.process( generated.sqltext, include_table=False, literal_binds=True ) if generated.persisted is True: text += " STORED" elif generated.persisted is False: text += " VIRTUAL" return text def visit_identity_column(self, identity, **kw): text = "GENERATED %s AS IDENTITY" % ( "ALWAYS" if identity.always else "BY DEFAULT", ) options = self.get_identity_options(identity) if options: text += " (%s)" % options return text class GenericTypeCompiler(TypeCompiler): def visit_FLOAT(self, type_, **kw): return "FLOAT" def visit_REAL(self, type_, **kw): return "REAL" def visit_NUMERIC(self, type_, **kw): if type_.precision is None: return "NUMERIC" elif type_.scale is None: return "NUMERIC(%(precision)s)" % {"precision": type_.precision} else: return "NUMERIC(%(precision)s, %(scale)s)" % { "precision": type_.precision, "scale": type_.scale, } def visit_DECIMAL(self, type_, **kw): if type_.precision is None: return "DECIMAL" elif type_.scale is None: return "DECIMAL(%(precision)s)" % {"precision": type_.precision} else: return "DECIMAL(%(precision)s, %(scale)s)" % { "precision": type_.precision, "scale": type_.scale, } def visit_INTEGER(self, type_, **kw): return "INTEGER" def visit_SMALLINT(self, type_, **kw): return "SMALLINT" def visit_BIGINT(self, type_, **kw): return "BIGINT" def visit_TIMESTAMP(self, type_, **kw): return "TIMESTAMP" def visit_DATETIME(self, type_, **kw): return "DATETIME" def visit_DATE(self, type_, **kw): return "DATE" def visit_TIME(self, type_, **kw): return "TIME" def visit_CLOB(self, type_, **kw): return "CLOB" def visit_NCLOB(self, type_, **kw): return "NCLOB" def _render_string_type(self, type_, name): text = name if type_.length: text += "(%d)" % type_.length if type_.collation: text += ' COLLATE "%s"' % type_.collation return text def visit_CHAR(self, type_, **kw): return self._render_string_type(type_, "CHAR") def visit_NCHAR(self, type_, **kw): return self._render_string_type(type_, "NCHAR") def visit_VARCHAR(self, type_, **kw): return self._render_string_type(type_, "VARCHAR") def visit_NVARCHAR(self, type_, **kw): return self._render_string_type(type_, "NVARCHAR") def visit_TEXT(self, type_, **kw): return self._render_string_type(type_, "TEXT") def visit_BLOB(self, type_, **kw): return "BLOB" def visit_BINARY(self, type_, **kw): return "BINARY" + (type_.length and "(%d)" % type_.length or "") def visit_VARBINARY(self, type_, **kw): return "VARBINARY" + (type_.length and "(%d)" % type_.length or "") def visit_BOOLEAN(self, type_, **kw): return "BOOLEAN" def visit_large_binary(self, type_, **kw): return self.visit_BLOB(type_, **kw) def visit_boolean(self, type_, **kw): return self.visit_BOOLEAN(type_, **kw) def visit_time(self, type_, **kw): return self.visit_TIME(type_, **kw) def visit_datetime(self, type_, **kw): return self.visit_DATETIME(type_, **kw) def visit_date(self, type_, **kw): return self.visit_DATE(type_, **kw) def visit_big_integer(self, type_, **kw): return self.visit_BIGINT(type_, **kw) def visit_small_integer(self, type_, **kw): return self.visit_SMALLINT(type_, **kw) def visit_integer(self, type_, **kw): return self.visit_INTEGER(type_, **kw) def visit_real(self, type_, **kw): return self.visit_REAL(type_, **kw) def visit_float(self, type_, **kw): return self.visit_FLOAT(type_, **kw) def visit_numeric(self, type_, **kw): return self.visit_NUMERIC(type_, **kw) def visit_string(self, type_, **kw): return self.visit_VARCHAR(type_, **kw) def visit_unicode(self, type_, **kw): return self.visit_VARCHAR(type_, **kw) def visit_text(self, type_, **kw): return self.visit_TEXT(type_, **kw) def visit_unicode_text(self, type_, **kw): return self.visit_TEXT(type_, **kw) def visit_enum(self, type_, **kw): return self.visit_VARCHAR(type_, **kw) def visit_null(self, type_, **kw): raise exc.CompileError( "Can't generate DDL for %r; " "did you forget to specify a " "type on this Column?" % type_ ) def visit_type_decorator(self, type_, **kw): return self.process(type_.type_engine(self.dialect), **kw) def visit_user_defined(self, type_, **kw): return type_.get_col_spec(**kw) class StrSQLTypeCompiler(GenericTypeCompiler): def process(self, type_, **kw): try: _compiler_dispatch = type_._compiler_dispatch except AttributeError: return self._visit_unknown(type_, **kw) else: return _compiler_dispatch(self, **kw) def __getattr__(self, key): if key.startswith("visit_"): return self._visit_unknown else: raise AttributeError(key) def _visit_unknown(self, type_, **kw): if type_.__class__.__name__ == type_.__class__.__name__.upper(): return type_.__class__.__name__ else: return repr(type_) def visit_null(self, type_, **kw): return "NULL" def visit_user_defined(self, type_, **kw): try: get_col_spec = type_.get_col_spec except AttributeError: return repr(type_) else: return get_col_spec(**kw) class IdentifierPreparer(object): """Handle quoting and case-folding of identifiers based on options.""" reserved_words = RESERVED_WORDS legal_characters = LEGAL_CHARACTERS illegal_initial_characters = ILLEGAL_INITIAL_CHARACTERS schema_for_object = operator.attrgetter("schema") """Return the .schema attribute for an object. For the default IdentifierPreparer, the schema for an object is always the value of the ".schema" attribute. if the preparer is replaced with one that has a non-empty schema_translate_map, the value of the ".schema" attribute is rendered a symbol that will be converted to a real schema name from the mapping post-compile. """ def __init__( self, dialect, initial_quote='"', final_quote=None, escape_quote='"', quote_case_sensitive_collations=True, omit_schema=False, ): """Construct a new ``IdentifierPreparer`` object. initial_quote Character that begins a delimited identifier. final_quote Character that ends a delimited identifier. Defaults to `initial_quote`. omit_schema Prevent prepending schema name. Useful for databases that do not support schemae. """ self.dialect = dialect self.initial_quote = initial_quote self.final_quote = final_quote or self.initial_quote self.escape_quote = escape_quote self.escape_to_quote = self.escape_quote * 2 self.omit_schema = omit_schema self.quote_case_sensitive_collations = quote_case_sensitive_collations self._strings = {} self._double_percents = self.dialect.paramstyle in ( "format", "pyformat", ) def _with_schema_translate(self, schema_translate_map): prep = self.__class__.__new__(self.__class__) prep.__dict__.update(self.__dict__) def symbol_getter(obj): name = obj.schema if name in schema_translate_map and obj._use_schema_map: if name is not None and ("[" in name or "]" in name): raise exc.CompileError( "Square bracket characters ([]) not supported " "in schema translate name '%s'" % name ) return quoted_name( "__[SCHEMA_%s]" % (name or "_none"), quote=False ) else: return obj.schema prep.schema_for_object = symbol_getter return prep def _render_schema_translates(self, statement, schema_translate_map): d = schema_translate_map if None in d: d["_none"] = d[None] def replace(m): name = m.group(2) effective_schema = d[name] if not effective_schema: effective_schema = self.dialect.default_schema_name if not effective_schema: # TODO: no coverage here raise exc.CompileError( "Dialect has no default schema name; can't " "use None as dynamic schema target." ) return self.quote_schema(effective_schema) return re.sub(r"(__\[SCHEMA_([^\]]+)\])", replace, statement) def _escape_identifier(self, value): """Escape an identifier. Subclasses should override this to provide database-dependent escaping behavior. """ value = value.replace(self.escape_quote, self.escape_to_quote) if self._double_percents: value = value.replace("%", "%%") return value def _unescape_identifier(self, value): """Canonicalize an escaped identifier. Subclasses should override this to provide database-dependent unescaping behavior that reverses _escape_identifier. """ return value.replace(self.escape_to_quote, self.escape_quote) def validate_sql_phrase(self, element, reg): """keyword sequence filter. a filter for elements that are intended to represent keyword sequences, such as "INITIALLY", "INITIALLY DEFERRED", etc. no special characters should be present. .. versionadded:: 1.3 """ if element is not None and not reg.match(element): raise exc.CompileError( "Unexpected SQL phrase: %r (matching against %r)" % (element, reg.pattern) ) return element def quote_identifier(self, value): """Quote an identifier. Subclasses should override this to provide database-dependent quoting behavior. """ return ( self.initial_quote + self._escape_identifier(value) + self.final_quote ) def _requires_quotes(self, value): """Return True if the given identifier requires quoting.""" lc_value = value.lower() return ( lc_value in self.reserved_words or value[0] in self.illegal_initial_characters or not self.legal_characters.match(util.text_type(value)) or (lc_value != value) ) def _requires_quotes_illegal_chars(self, value): """Return True if the given identifier requires quoting, but not taking case convention into account.""" return not self.legal_characters.match(util.text_type(value)) def quote_schema(self, schema, force=None): """Conditionally quote a schema name. The name is quoted if it is a reserved word, contains quote-necessary characters, or is an instance of :class:`.quoted_name` which includes ``quote`` set to ``True``. Subclasses can override this to provide database-dependent quoting behavior for schema names. :param schema: string schema name :param force: unused .. deprecated:: 0.9 The :paramref:`.IdentifierPreparer.quote_schema.force` parameter is deprecated and will be removed in a future release. This flag has no effect on the behavior of the :meth:`.IdentifierPreparer.quote` method; please refer to :class:`.quoted_name`. """ if force is not None: # not using the util.deprecated_params() decorator in this # case because of the additional function call overhead on this # very performance-critical spot. util.warn_deprecated( "The IdentifierPreparer.quote_schema.force parameter is " "deprecated and will be removed in a future release. This " "flag has no effect on the behavior of the " "IdentifierPreparer.quote method; please refer to " "quoted_name().", # deprecated 0.9. warning from 1.3 version="0.9", ) return self.quote(schema) def quote(self, ident, force=None): """Conditionally quote an identifier. The identifier is quoted if it is a reserved word, contains quote-necessary characters, or is an instance of :class:`.quoted_name` which includes ``quote`` set to ``True``. Subclasses can override this to provide database-dependent quoting behavior for identifier names. :param ident: string identifier :param force: unused .. deprecated:: 0.9 The :paramref:`.IdentifierPreparer.quote.force` parameter is deprecated and will be removed in a future release. This flag has no effect on the behavior of the :meth:`.IdentifierPreparer.quote` method; please refer to :class:`.quoted_name`. """ if force is not None: # not using the util.deprecated_params() decorator in this # case because of the additional function call overhead on this # very performance-critical spot. util.warn_deprecated( "The IdentifierPreparer.quote.force parameter is " "deprecated and will be removed in a future release. This " "flag has no effect on the behavior of the " "IdentifierPreparer.quote method; please refer to " "quoted_name().", # deprecated 0.9. warning from 1.3 version="0.9", ) force = getattr(ident, "quote", None) if force is None: if ident in self._strings: return self._strings[ident] else: if self._requires_quotes(ident): self._strings[ident] = self.quote_identifier(ident) else: self._strings[ident] = ident return self._strings[ident] elif force: return self.quote_identifier(ident) else: return ident def format_collation(self, collation_name): if self.quote_case_sensitive_collations: return self.quote(collation_name) else: return collation_name def format_sequence(self, sequence, use_schema=True): name = self.quote(sequence.name) effective_schema = self.schema_for_object(sequence) if ( not self.omit_schema and use_schema and effective_schema is not None ): name = self.quote_schema(effective_schema) + "." + name return name def format_label(self, label, name=None): return self.quote(name or label.name) def format_alias(self, alias, name=None): return self.quote(name or alias.name) def format_savepoint(self, savepoint, name=None): # Running the savepoint name through quoting is unnecessary # for all known dialects. This is here to support potential # third party use cases ident = name or savepoint.ident if self._requires_quotes(ident): ident = self.quote_identifier(ident) return ident @util.preload_module("sqlalchemy.sql.naming") def format_constraint(self, constraint, _alembic_quote=True): naming = util.preloaded.sql_naming if constraint.name is elements._NONE_NAME: name = naming._constraint_name_for_table( constraint, constraint.table ) if name is None: return None else: name = constraint.name if constraint.__visit_name__ == "index": return self.truncate_and_render_index_name( name, _alembic_quote=_alembic_quote ) else: return self.truncate_and_render_constraint_name( name, _alembic_quote=_alembic_quote ) def truncate_and_render_index_name(self, name, _alembic_quote=True): # calculate these at format time so that ad-hoc changes # to dialect.max_identifier_length etc. can be reflected # as IdentifierPreparer is long lived max_ = ( self.dialect.max_index_name_length or self.dialect.max_identifier_length ) return self._truncate_and_render_maxlen_name( name, max_, _alembic_quote ) def truncate_and_render_constraint_name(self, name, _alembic_quote=True): # calculate these at format time so that ad-hoc changes # to dialect.max_identifier_length etc. can be reflected # as IdentifierPreparer is long lived max_ = ( self.dialect.max_constraint_name_length or self.dialect.max_identifier_length ) return self._truncate_and_render_maxlen_name( name, max_, _alembic_quote ) def _truncate_and_render_maxlen_name(self, name, max_, _alembic_quote): if isinstance(name, elements._truncated_label): if len(name) > max_: name = name[0 : max_ - 8] + "_" + util.md5_hex(name)[-4:] else: self.dialect.validate_identifier(name) if not _alembic_quote: return name else: return self.quote(name) def format_index(self, index): return self.format_constraint(index) def format_table(self, table, use_schema=True, name=None): """Prepare a quoted table and schema name.""" if name is None: name = table.name result = self.quote(name) effective_schema = self.schema_for_object(table) if not self.omit_schema and use_schema and effective_schema: result = self.quote_schema(effective_schema) + "." + result return result def format_schema(self, name): """Prepare a quoted schema name.""" return self.quote(name) def format_label_name( self, name, anon_map=None, ): """Prepare a quoted column name.""" if anon_map is not None and isinstance( name, elements._truncated_label ): name = name.apply_map(anon_map) return self.quote(name) def format_column( self, column, use_table=False, name=None, table_name=None, use_schema=False, anon_map=None, ): """Prepare a quoted column name.""" if name is None: name = column.name if anon_map is not None and isinstance( name, elements._truncated_label ): name = name.apply_map(anon_map) if not getattr(column, "is_literal", False): if use_table: return ( self.format_table( column.table, use_schema=use_schema, name=table_name ) + "." + self.quote(name) ) else: return self.quote(name) else: # literal textual elements get stuck into ColumnClause a lot, # which shouldn't get quoted if use_table: return ( self.format_table( column.table, use_schema=use_schema, name=table_name ) + "." + name ) else: return name def format_table_seq(self, table, use_schema=True): """Format table name and schema as a tuple.""" # Dialects with more levels in their fully qualified references # ('database', 'owner', etc.) could override this and return # a longer sequence. effective_schema = self.schema_for_object(table) if not self.omit_schema and use_schema and effective_schema: return ( self.quote_schema(effective_schema), self.format_table(table, use_schema=False), ) else: return (self.format_table(table, use_schema=False),) @util.memoized_property def _r_identifiers(self): initial, final, escaped_final = [ re.escape(s) for s in ( self.initial_quote, self.final_quote, self._escape_identifier(self.final_quote), ) ] r = re.compile( r"(?:" r"(?:%(initial)s((?:%(escaped)s|[^%(final)s])+)%(final)s" r"|([^\.]+))(?=\.|$))+" % {"initial": initial, "final": final, "escaped": escaped_final} ) return r def unformat_identifiers(self, identifiers): """Unpack 'schema.table.column'-like strings into components.""" r = self._r_identifiers return [ self._unescape_identifier(i) for i in [a or b for a, b in r.findall(identifiers)] ]