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+# orm/query.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
+
+"""The Query class and support.
+
+Defines the :class:`_query.Query` class, the central
+construct used by the ORM to construct database queries.
+
+The :class:`_query.Query` class should not be confused with the
+:class:`_expression.Select` class, which defines database
+SELECT operations at the SQL (non-ORM) level. ``Query`` differs from
+``Select`` in that it returns ORM-mapped objects and interacts with an
+ORM session, whereas the ``Select`` construct interacts directly with the
+database to return iterable result sets.
+
+"""
+from __future__ import annotations
+
+import collections.abc as collections_abc
+import operator
+from typing import Any
+from typing import Callable
+from typing import cast
+from typing import Dict
+from typing import Generic
+from typing import Iterable
+from typing import Iterator
+from typing import List
+from typing import Mapping
+from typing import Optional
+from typing import overload
+from typing import Sequence
+from typing import Tuple
+from typing import Type
+from typing import TYPE_CHECKING
+from typing import TypeVar
+from typing import Union
+
+from . import attributes
+from . import interfaces
+from . import loading
+from . import util as orm_util
+from ._typing import _O
+from .base import _assertions
+from .context import _column_descriptions
+from .context import _determine_last_joined_entity
+from .context import _legacy_filter_by_entity_zero
+from .context import FromStatement
+from .context import ORMCompileState
+from .context import QueryContext
+from .interfaces import ORMColumnDescription
+from .interfaces import ORMColumnsClauseRole
+from .util import AliasedClass
+from .util import object_mapper
+from .util import with_parent
+from .. import exc as sa_exc
+from .. import inspect
+from .. import inspection
+from .. import log
+from .. import sql
+from .. import util
+from ..engine import Result
+from ..engine import Row
+from ..event import dispatcher
+from ..event import EventTarget
+from ..sql import coercions
+from ..sql import expression
+from ..sql import roles
+from ..sql import Select
+from ..sql import util as sql_util
+from ..sql import visitors
+from ..sql._typing import _FromClauseArgument
+from ..sql._typing import _TP
+from ..sql.annotation import SupportsCloneAnnotations
+from ..sql.base import _entity_namespace_key
+from ..sql.base import _generative
+from ..sql.base import _NoArg
+from ..sql.base import Executable
+from ..sql.base import Generative
+from ..sql.elements import BooleanClauseList
+from ..sql.expression import Exists
+from ..sql.selectable import _MemoizedSelectEntities
+from ..sql.selectable import _SelectFromElements
+from ..sql.selectable import ForUpdateArg
+from ..sql.selectable import HasHints
+from ..sql.selectable import HasPrefixes
+from ..sql.selectable import HasSuffixes
+from ..sql.selectable import LABEL_STYLE_TABLENAME_PLUS_COL
+from ..sql.selectable import SelectLabelStyle
+from ..util.typing import Literal
+from ..util.typing import Self
+
+
+if TYPE_CHECKING:
+ from ._typing import _EntityType
+ from ._typing import _ExternalEntityType
+ from ._typing import _InternalEntityType
+ from ._typing import SynchronizeSessionArgument
+ from .mapper import Mapper
+ from .path_registry import PathRegistry
+ from .session import _PKIdentityArgument
+ from .session import Session
+ from .state import InstanceState
+ from ..engine.cursor import CursorResult
+ from ..engine.interfaces import _ImmutableExecuteOptions
+ from ..engine.interfaces import CompiledCacheType
+ from ..engine.interfaces import IsolationLevel
+ from ..engine.interfaces import SchemaTranslateMapType
+ from ..engine.result import FrozenResult
+ from ..engine.result import ScalarResult
+ from ..sql._typing import _ColumnExpressionArgument
+ from ..sql._typing import _ColumnExpressionOrStrLabelArgument
+ from ..sql._typing import _ColumnsClauseArgument
+ from ..sql._typing import _DMLColumnArgument
+ from ..sql._typing import _JoinTargetArgument
+ from ..sql._typing import _LimitOffsetType
+ from ..sql._typing import _MAYBE_ENTITY
+ from ..sql._typing import _no_kw
+ from ..sql._typing import _NOT_ENTITY
+ from ..sql._typing import _OnClauseArgument
+ from ..sql._typing import _PropagateAttrsType
+ from ..sql._typing import _T0
+ from ..sql._typing import _T1
+ from ..sql._typing import _T2
+ from ..sql._typing import _T3
+ from ..sql._typing import _T4
+ from ..sql._typing import _T5
+ from ..sql._typing import _T6
+ from ..sql._typing import _T7
+ from ..sql._typing import _TypedColumnClauseArgument as _TCCA
+ from ..sql.base import CacheableOptions
+ from ..sql.base import ExecutableOption
+ from ..sql.elements import ColumnElement
+ from ..sql.elements import Label
+ from ..sql.selectable import _ForUpdateOfArgument
+ from ..sql.selectable import _JoinTargetElement
+ from ..sql.selectable import _SetupJoinsElement
+ from ..sql.selectable import Alias
+ from ..sql.selectable import CTE
+ from ..sql.selectable import ExecutableReturnsRows
+ from ..sql.selectable import FromClause
+ from ..sql.selectable import ScalarSelect
+ from ..sql.selectable import Subquery
+
+
+__all__ = ["Query", "QueryContext"]
+
+_T = TypeVar("_T", bound=Any)
+
+
+@inspection._self_inspects
+@log.class_logger
+class Query(
+ _SelectFromElements,
+ SupportsCloneAnnotations,
+ HasPrefixes,
+ HasSuffixes,
+ HasHints,
+ EventTarget,
+ log.Identified,
+ Generative,
+ Executable,
+ Generic[_T],
+):
+ """ORM-level SQL construction object.
+
+ .. legacy:: The ORM :class:`.Query` object is a legacy construct
+ as of SQLAlchemy 2.0. See the notes at the top of
+ :ref:`query_api_toplevel` for an overview, including links to migration
+ documentation.
+
+ :class:`_query.Query` objects are normally initially generated using the
+ :meth:`~.Session.query` method of :class:`.Session`, and in
+ less common cases by instantiating the :class:`_query.Query` directly and
+ associating with a :class:`.Session` using the
+ :meth:`_query.Query.with_session`
+ method.
+
+ """
+
+ # elements that are in Core and can be cached in the same way
+ _where_criteria: Tuple[ColumnElement[Any], ...] = ()
+ _having_criteria: Tuple[ColumnElement[Any], ...] = ()
+
+ _order_by_clauses: Tuple[ColumnElement[Any], ...] = ()
+ _group_by_clauses: Tuple[ColumnElement[Any], ...] = ()
+ _limit_clause: Optional[ColumnElement[Any]] = None
+ _offset_clause: Optional[ColumnElement[Any]] = None
+
+ _distinct: bool = False
+ _distinct_on: Tuple[ColumnElement[Any], ...] = ()
+
+ _for_update_arg: Optional[ForUpdateArg] = None
+ _correlate: Tuple[FromClause, ...] = ()
+ _auto_correlate: bool = True
+ _from_obj: Tuple[FromClause, ...] = ()
+ _setup_joins: Tuple[_SetupJoinsElement, ...] = ()
+
+ _label_style: SelectLabelStyle = SelectLabelStyle.LABEL_STYLE_LEGACY_ORM
+
+ _memoized_select_entities = ()
+
+ _compile_options: Union[Type[CacheableOptions], CacheableOptions] = (
+ ORMCompileState.default_compile_options
+ )
+
+ _with_options: Tuple[ExecutableOption, ...]
+ load_options = QueryContext.default_load_options + {
+ "_legacy_uniquing": True
+ }
+
+ _params: util.immutabledict[str, Any] = util.EMPTY_DICT
+
+ # local Query builder state, not needed for
+ # compilation or execution
+ _enable_assertions = True
+
+ _statement: Optional[ExecutableReturnsRows] = None
+
+ session: Session
+
+ dispatch: dispatcher[Query[_T]]
+
+ # mirrors that of ClauseElement, used to propagate the "orm"
+ # plugin as well as the "subject" of the plugin, e.g. the mapper
+ # we are querying against.
+ @util.memoized_property
+ def _propagate_attrs(self) -> _PropagateAttrsType:
+ return util.EMPTY_DICT
+
+ def __init__(
+ self,
+ entities: Union[
+ _ColumnsClauseArgument[Any], Sequence[_ColumnsClauseArgument[Any]]
+ ],
+ session: Optional[Session] = None,
+ ):
+ """Construct a :class:`_query.Query` directly.
+
+ E.g.::
+
+ q = Query([User, Address], session=some_session)
+
+ The above is equivalent to::
+
+ q = some_session.query(User, Address)
+
+ :param entities: a sequence of entities and/or SQL expressions.
+
+ :param session: a :class:`.Session` with which the
+ :class:`_query.Query`
+ will be associated. Optional; a :class:`_query.Query`
+ can be associated
+ with a :class:`.Session` generatively via the
+ :meth:`_query.Query.with_session` method as well.
+
+ .. seealso::
+
+ :meth:`.Session.query`
+
+ :meth:`_query.Query.with_session`
+
+ """
+
+ # session is usually present. There's one case in subqueryloader
+ # where it stores a Query without a Session and also there are tests
+ # for the query(Entity).with_session(session) API which is likely in
+ # some old recipes, however these are legacy as select() can now be
+ # used.
+ self.session = session # type: ignore
+ self._set_entities(entities)
+
+ def _set_propagate_attrs(self, values: Mapping[str, Any]) -> Self:
+ self._propagate_attrs = util.immutabledict(values)
+ return self
+
+ def _set_entities(
+ self,
+ entities: Union[
+ _ColumnsClauseArgument[Any], Iterable[_ColumnsClauseArgument[Any]]
+ ],
+ ) -> None:
+ self._raw_columns = [
+ coercions.expect(
+ roles.ColumnsClauseRole,
+ ent,
+ apply_propagate_attrs=self,
+ post_inspect=True,
+ )
+ for ent in util.to_list(entities)
+ ]
+
+ def tuples(self: Query[_O]) -> Query[Tuple[_O]]:
+ """return a tuple-typed form of this :class:`.Query`.
+
+ This method invokes the :meth:`.Query.only_return_tuples`
+ method with a value of ``True``, which by itself ensures that this
+ :class:`.Query` will always return :class:`.Row` objects, even
+ if the query is made against a single entity. It then also
+ at the typing level will return a "typed" query, if possible,
+ that will type result rows as ``Tuple`` objects with typed
+ elements.
+
+ This method can be compared to the :meth:`.Result.tuples` method,
+ which returns "self", but from a typing perspective returns an object
+ that will yield typed ``Tuple`` objects for results. Typing
+ takes effect only if this :class:`.Query` object is a typed
+ query object already.
+
+ .. versionadded:: 2.0
+
+ .. seealso::
+
+ :meth:`.Result.tuples` - v2 equivalent method.
+
+ """
+ return self.only_return_tuples(True) # type: ignore
+
+ def _entity_from_pre_ent_zero(self) -> Optional[_InternalEntityType[Any]]:
+ if not self._raw_columns:
+ return None
+
+ ent = self._raw_columns[0]
+
+ if "parententity" in ent._annotations:
+ return ent._annotations["parententity"] # type: ignore
+ elif "bundle" in ent._annotations:
+ return ent._annotations["bundle"] # type: ignore
+ else:
+ # label, other SQL expression
+ for element in visitors.iterate(ent):
+ if "parententity" in element._annotations:
+ return element._annotations["parententity"] # type: ignore # noqa: E501
+ else:
+ return None
+
+ def _only_full_mapper_zero(self, methname: str) -> Mapper[Any]:
+ if (
+ len(self._raw_columns) != 1
+ or "parententity" not in self._raw_columns[0]._annotations
+ or not self._raw_columns[0].is_selectable
+ ):
+ raise sa_exc.InvalidRequestError(
+ "%s() can only be used against "
+ "a single mapped class." % methname
+ )
+
+ return self._raw_columns[0]._annotations["parententity"] # type: ignore # noqa: E501
+
+ def _set_select_from(
+ self, obj: Iterable[_FromClauseArgument], set_base_alias: bool
+ ) -> None:
+ fa = [
+ coercions.expect(
+ roles.StrictFromClauseRole,
+ elem,
+ allow_select=True,
+ apply_propagate_attrs=self,
+ )
+ for elem in obj
+ ]
+
+ self._compile_options += {"_set_base_alias": set_base_alias}
+ self._from_obj = tuple(fa)
+
+ @_generative
+ def _set_lazyload_from(self, state: InstanceState[Any]) -> Self:
+ self.load_options += {"_lazy_loaded_from": state}
+ return self
+
+ def _get_condition(self) -> None:
+ """used by legacy BakedQuery"""
+ self._no_criterion_condition("get", order_by=False, distinct=False)
+
+ def _get_existing_condition(self) -> None:
+ self._no_criterion_assertion("get", order_by=False, distinct=False)
+
+ def _no_criterion_assertion(
+ self, meth: str, order_by: bool = True, distinct: bool = True
+ ) -> None:
+ if not self._enable_assertions:
+ return
+ if (
+ self._where_criteria
+ or self._statement is not None
+ or self._from_obj
+ or self._setup_joins
+ or self._limit_clause is not None
+ or self._offset_clause is not None
+ or self._group_by_clauses
+ or (order_by and self._order_by_clauses)
+ or (distinct and self._distinct)
+ ):
+ raise sa_exc.InvalidRequestError(
+ "Query.%s() being called on a "
+ "Query with existing criterion. " % meth
+ )
+
+ def _no_criterion_condition(
+ self, meth: str, order_by: bool = True, distinct: bool = True
+ ) -> None:
+ self._no_criterion_assertion(meth, order_by, distinct)
+
+ self._from_obj = self._setup_joins = ()
+ if self._statement is not None:
+ self._compile_options += {"_statement": None}
+ self._where_criteria = ()
+ self._distinct = False
+
+ self._order_by_clauses = self._group_by_clauses = ()
+
+ def _no_clauseelement_condition(self, meth: str) -> None:
+ if not self._enable_assertions:
+ return
+ if self._order_by_clauses:
+ raise sa_exc.InvalidRequestError(
+ "Query.%s() being called on a "
+ "Query with existing criterion. " % meth
+ )
+ self._no_criterion_condition(meth)
+
+ def _no_statement_condition(self, meth: str) -> None:
+ if not self._enable_assertions:
+ return
+ if self._statement is not None:
+ raise sa_exc.InvalidRequestError(
+ (
+ "Query.%s() being called on a Query with an existing full "
+ "statement - can't apply criterion."
+ )
+ % meth
+ )
+
+ def _no_limit_offset(self, meth: str) -> None:
+ if not self._enable_assertions:
+ return
+ if self._limit_clause is not None or self._offset_clause is not None:
+ raise sa_exc.InvalidRequestError(
+ "Query.%s() being called on a Query which already has LIMIT "
+ "or OFFSET applied. Call %s() before limit() or offset() "
+ "are applied." % (meth, meth)
+ )
+
+ @property
+ def _has_row_limiting_clause(self) -> bool:
+ return (
+ self._limit_clause is not None or self._offset_clause is not None
+ )
+
+ def _get_options(
+ self,
+ populate_existing: Optional[bool] = None,
+ version_check: Optional[bool] = None,
+ only_load_props: Optional[Sequence[str]] = None,
+ refresh_state: Optional[InstanceState[Any]] = None,
+ identity_token: Optional[Any] = None,
+ ) -> Self:
+ load_options: Dict[str, Any] = {}
+ compile_options: Dict[str, Any] = {}
+
+ if version_check:
+ load_options["_version_check"] = version_check
+ if populate_existing:
+ load_options["_populate_existing"] = populate_existing
+ if refresh_state:
+ load_options["_refresh_state"] = refresh_state
+ compile_options["_for_refresh_state"] = True
+ if only_load_props:
+ compile_options["_only_load_props"] = frozenset(only_load_props)
+ if identity_token:
+ load_options["_identity_token"] = identity_token
+
+ if load_options:
+ self.load_options += load_options
+ if compile_options:
+ self._compile_options += compile_options
+
+ return self
+
+ def _clone(self, **kw: Any) -> Self:
+ return self._generate()
+
+ def _get_select_statement_only(self) -> Select[_T]:
+ if self._statement is not None:
+ raise sa_exc.InvalidRequestError(
+ "Can't call this method on a Query that uses from_statement()"
+ )
+ return cast("Select[_T]", self.statement)
+
+ @property
+ def statement(self) -> Union[Select[_T], FromStatement[_T]]:
+ """The full SELECT statement represented by this Query.
+
+ The statement by default will not have disambiguating labels
+ applied to the construct unless with_labels(True) is called
+ first.
+
+ """
+
+ # .statement can return the direct future.Select() construct here, as
+ # long as we are not using subsequent adaption features that
+ # are made against raw entities, e.g. from_self(), with_polymorphic(),
+ # select_entity_from(). If these features are being used, then
+ # the Select() we return will not have the correct .selected_columns
+ # collection and will not embed in subsequent queries correctly.
+ # We could find a way to make this collection "correct", however
+ # this would not be too different from doing the full compile as
+ # we are doing in any case, the Select() would still not have the
+ # proper state for other attributes like whereclause, order_by,
+ # and these features are all deprecated in any case.
+ #
+ # for these reasons, Query is not a Select, it remains an ORM
+ # object for which __clause_element__() must be called in order for
+ # it to provide a real expression object.
+ #
+ # from there, it starts to look much like Query itself won't be
+ # passed into the execute process and won't generate its own cache
+ # key; this will all occur in terms of the ORM-enabled Select.
+ if not self._compile_options._set_base_alias:
+ # if we don't have legacy top level aliasing features in use
+ # then convert to a future select() directly
+ stmt = self._statement_20(for_statement=True)
+ else:
+ stmt = self._compile_state(for_statement=True).statement
+
+ if self._params:
+ stmt = stmt.params(self._params)
+
+ return stmt
+
+ def _final_statement(self, legacy_query_style: bool = True) -> Select[Any]:
+ """Return the 'final' SELECT statement for this :class:`.Query`.
+
+ This is used by the testing suite only and is fairly inefficient.
+
+ This is the Core-only select() that will be rendered by a complete
+ compilation of this query, and is what .statement used to return
+ in 1.3.
+
+
+ """
+
+ q = self._clone()
+
+ return q._compile_state(
+ use_legacy_query_style=legacy_query_style
+ ).statement # type: ignore
+
+ def _statement_20(
+ self, for_statement: bool = False, use_legacy_query_style: bool = True
+ ) -> Union[Select[_T], FromStatement[_T]]:
+ # TODO: this event needs to be deprecated, as it currently applies
+ # only to ORM query and occurs at this spot that is now more
+ # or less an artificial spot
+ if self.dispatch.before_compile:
+ for fn in self.dispatch.before_compile:
+ new_query = fn(self)
+ if new_query is not None and new_query is not self:
+ self = new_query
+ if not fn._bake_ok: # type: ignore
+ self._compile_options += {"_bake_ok": False}
+
+ compile_options = self._compile_options
+ compile_options += {
+ "_for_statement": for_statement,
+ "_use_legacy_query_style": use_legacy_query_style,
+ }
+
+ stmt: Union[Select[_T], FromStatement[_T]]
+
+ if self._statement is not None:
+ stmt = FromStatement(self._raw_columns, self._statement)
+ stmt.__dict__.update(
+ _with_options=self._with_options,
+ _with_context_options=self._with_context_options,
+ _compile_options=compile_options,
+ _execution_options=self._execution_options,
+ _propagate_attrs=self._propagate_attrs,
+ )
+ else:
+ # Query / select() internal attributes are 99% cross-compatible
+ stmt = Select._create_raw_select(**self.__dict__)
+ stmt.__dict__.update(
+ _label_style=self._label_style,
+ _compile_options=compile_options,
+ _propagate_attrs=self._propagate_attrs,
+ )
+ stmt.__dict__.pop("session", None)
+
+ # ensure the ORM context is used to compile the statement, even
+ # if it has no ORM entities. This is so ORM-only things like
+ # _legacy_joins are picked up that wouldn't be picked up by the
+ # Core statement context
+ if "compile_state_plugin" not in stmt._propagate_attrs:
+ stmt._propagate_attrs = stmt._propagate_attrs.union(
+ {"compile_state_plugin": "orm", "plugin_subject": None}
+ )
+
+ return stmt
+
+ def subquery(
+ self,
+ name: Optional[str] = None,
+ with_labels: bool = False,
+ reduce_columns: bool = False,
+ ) -> Subquery:
+ """Return the full SELECT statement represented by
+ this :class:`_query.Query`, embedded within an
+ :class:`_expression.Alias`.
+
+ Eager JOIN generation within the query is disabled.
+
+ .. seealso::
+
+ :meth:`_sql.Select.subquery` - v2 comparable method.
+
+ :param name: string name to be assigned as the alias;
+ this is passed through to :meth:`_expression.FromClause.alias`.
+ If ``None``, a name will be deterministically generated
+ at compile time.
+
+ :param with_labels: if True, :meth:`.with_labels` will be called
+ on the :class:`_query.Query` first to apply table-qualified labels
+ to all columns.
+
+ :param reduce_columns: if True,
+ :meth:`_expression.Select.reduce_columns` will
+ be called on the resulting :func:`_expression.select` construct,
+ to remove same-named columns where one also refers to the other
+ via foreign key or WHERE clause equivalence.
+
+ """
+ q = self.enable_eagerloads(False)
+ if with_labels:
+ q = q.set_label_style(LABEL_STYLE_TABLENAME_PLUS_COL)
+
+ stmt = q._get_select_statement_only()
+
+ if TYPE_CHECKING:
+ assert isinstance(stmt, Select)
+
+ if reduce_columns:
+ stmt = stmt.reduce_columns()
+ return stmt.subquery(name=name)
+
+ def cte(
+ self,
+ name: Optional[str] = None,
+ recursive: bool = False,
+ nesting: bool = False,
+ ) -> CTE:
+ r"""Return the full SELECT statement represented by this
+ :class:`_query.Query` represented as a common table expression (CTE).
+
+ Parameters and usage are the same as those of the
+ :meth:`_expression.SelectBase.cte` method; see that method for
+ further details.
+
+ Here is the `PostgreSQL WITH
+ RECURSIVE example
+ <https://www.postgresql.org/docs/current/static/queries-with.html>`_.
+ Note that, in this example, the ``included_parts`` cte and the
+ ``incl_alias`` alias of it are Core selectables, which
+ means the columns are accessed via the ``.c.`` attribute. The
+ ``parts_alias`` object is an :func:`_orm.aliased` instance of the
+ ``Part`` entity, so column-mapped attributes are available
+ directly::
+
+ from sqlalchemy.orm import aliased
+
+ class Part(Base):
+ __tablename__ = 'part'
+ part = Column(String, primary_key=True)
+ sub_part = Column(String, primary_key=True)
+ quantity = Column(Integer)
+
+ included_parts = session.query(
+ Part.sub_part,
+ Part.part,
+ Part.quantity).\
+ filter(Part.part=="our part").\
+ cte(name="included_parts", recursive=True)
+
+ incl_alias = aliased(included_parts, name="pr")
+ parts_alias = aliased(Part, name="p")
+ included_parts = included_parts.union_all(
+ session.query(
+ parts_alias.sub_part,
+ parts_alias.part,
+ parts_alias.quantity).\
+ filter(parts_alias.part==incl_alias.c.sub_part)
+ )
+
+ q = session.query(
+ included_parts.c.sub_part,
+ func.sum(included_parts.c.quantity).
+ label('total_quantity')
+ ).\
+ group_by(included_parts.c.sub_part)
+
+ .. seealso::
+
+ :meth:`_sql.Select.cte` - v2 equivalent method.
+
+ """
+ return (
+ self.enable_eagerloads(False)
+ ._get_select_statement_only()
+ .cte(name=name, recursive=recursive, nesting=nesting)
+ )
+
+ def label(self, name: Optional[str]) -> Label[Any]:
+ """Return the full SELECT statement represented by this
+ :class:`_query.Query`, converted
+ to a scalar subquery with a label of the given name.
+
+ .. seealso::
+
+ :meth:`_sql.Select.label` - v2 comparable method.
+
+ """
+
+ return (
+ self.enable_eagerloads(False)
+ ._get_select_statement_only()
+ .label(name)
+ )
+
+ @overload
+ def as_scalar(
+ self: Query[Tuple[_MAYBE_ENTITY]],
+ ) -> ScalarSelect[_MAYBE_ENTITY]: ...
+
+ @overload
+ def as_scalar(
+ self: Query[Tuple[_NOT_ENTITY]],
+ ) -> ScalarSelect[_NOT_ENTITY]: ...
+
+ @overload
+ def as_scalar(self) -> ScalarSelect[Any]: ...
+
+ @util.deprecated(
+ "1.4",
+ "The :meth:`_query.Query.as_scalar` method is deprecated and will be "
+ "removed in a future release. Please refer to "
+ ":meth:`_query.Query.scalar_subquery`.",
+ )
+ def as_scalar(self) -> ScalarSelect[Any]:
+ """Return the full SELECT statement represented by this
+ :class:`_query.Query`, converted to a scalar subquery.
+
+ """
+ return self.scalar_subquery()
+
+ @overload
+ def scalar_subquery(
+ self: Query[Tuple[_MAYBE_ENTITY]],
+ ) -> ScalarSelect[Any]: ...
+
+ @overload
+ def scalar_subquery(
+ self: Query[Tuple[_NOT_ENTITY]],
+ ) -> ScalarSelect[_NOT_ENTITY]: ...
+
+ @overload
+ def scalar_subquery(self) -> ScalarSelect[Any]: ...
+
+ def scalar_subquery(self) -> ScalarSelect[Any]:
+ """Return the full SELECT statement represented by this
+ :class:`_query.Query`, converted to a scalar subquery.
+
+ Analogous to
+ :meth:`sqlalchemy.sql.expression.SelectBase.scalar_subquery`.
+
+ .. versionchanged:: 1.4 The :meth:`_query.Query.scalar_subquery`
+ method replaces the :meth:`_query.Query.as_scalar` method.
+
+ .. seealso::
+
+ :meth:`_sql.Select.scalar_subquery` - v2 comparable method.
+
+ """
+
+ return (
+ self.enable_eagerloads(False)
+ ._get_select_statement_only()
+ .scalar_subquery()
+ )
+
+ @property
+ def selectable(self) -> Union[Select[_T], FromStatement[_T]]:
+ """Return the :class:`_expression.Select` object emitted by this
+ :class:`_query.Query`.
+
+ Used for :func:`_sa.inspect` compatibility, this is equivalent to::
+
+ query.enable_eagerloads(False).with_labels().statement
+
+ """
+ return self.__clause_element__()
+
+ def __clause_element__(self) -> Union[Select[_T], FromStatement[_T]]:
+ return (
+ self._with_compile_options(
+ _enable_eagerloads=False, _render_for_subquery=True
+ )
+ .set_label_style(LABEL_STYLE_TABLENAME_PLUS_COL)
+ .statement
+ )
+
+ @overload
+ def only_return_tuples(
+ self: Query[_O], value: Literal[True]
+ ) -> RowReturningQuery[Tuple[_O]]: ...
+
+ @overload
+ def only_return_tuples(
+ self: Query[_O], value: Literal[False]
+ ) -> Query[_O]: ...
+
+ @_generative
+ def only_return_tuples(self, value: bool) -> Query[Any]:
+ """When set to True, the query results will always be a
+ :class:`.Row` object.
+
+ This can change a query that normally returns a single entity
+ as a scalar to return a :class:`.Row` result in all cases.
+
+ .. seealso::
+
+ :meth:`.Query.tuples` - returns tuples, but also at the typing
+ level will type results as ``Tuple``.
+
+ :meth:`_query.Query.is_single_entity`
+
+ :meth:`_engine.Result.tuples` - v2 comparable method.
+
+ """
+ self.load_options += dict(_only_return_tuples=value)
+ return self
+
+ @property
+ def is_single_entity(self) -> bool:
+ """Indicates if this :class:`_query.Query`
+ returns tuples or single entities.
+
+ Returns True if this query returns a single entity for each instance
+ in its result list, and False if this query returns a tuple of entities
+ for each result.
+
+ .. versionadded:: 1.3.11
+
+ .. seealso::
+
+ :meth:`_query.Query.only_return_tuples`
+
+ """
+ return (
+ not self.load_options._only_return_tuples
+ and len(self._raw_columns) == 1
+ and "parententity" in self._raw_columns[0]._annotations
+ and isinstance(
+ self._raw_columns[0]._annotations["parententity"],
+ ORMColumnsClauseRole,
+ )
+ )
+
+ @_generative
+ def enable_eagerloads(self, value: bool) -> Self:
+ """Control whether or not eager joins and subqueries are
+ rendered.
+
+ When set to False, the returned Query will not render
+ eager joins regardless of :func:`~sqlalchemy.orm.joinedload`,
+ :func:`~sqlalchemy.orm.subqueryload` options
+ or mapper-level ``lazy='joined'``/``lazy='subquery'``
+ configurations.
+
+ This is used primarily when nesting the Query's
+ statement into a subquery or other
+ selectable, or when using :meth:`_query.Query.yield_per`.
+
+ """
+ self._compile_options += {"_enable_eagerloads": value}
+ return self
+
+ @_generative
+ def _with_compile_options(self, **opt: Any) -> Self:
+ self._compile_options += opt
+ return self
+
+ @util.became_legacy_20(
+ ":meth:`_orm.Query.with_labels` and :meth:`_orm.Query.apply_labels`",
+ alternative="Use set_label_style(LABEL_STYLE_TABLENAME_PLUS_COL) "
+ "instead.",
+ )
+ def with_labels(self) -> Self:
+ return self.set_label_style(
+ SelectLabelStyle.LABEL_STYLE_TABLENAME_PLUS_COL
+ )
+
+ apply_labels = with_labels
+
+ @property
+ def get_label_style(self) -> SelectLabelStyle:
+ """
+ Retrieve the current label style.
+
+ .. versionadded:: 1.4
+
+ .. seealso::
+
+ :meth:`_sql.Select.get_label_style` - v2 equivalent method.
+
+ """
+ return self._label_style
+
+ def set_label_style(self, style: SelectLabelStyle) -> Self:
+ """Apply column labels to the return value of Query.statement.
+
+ Indicates that this Query's `statement` accessor should return
+ a SELECT statement that applies labels to all columns in the
+ form <tablename>_<columnname>; this is commonly used to
+ disambiguate columns from multiple tables which have the same
+ name.
+
+ When the `Query` actually issues SQL to load rows, it always
+ uses column labeling.
+
+ .. note:: The :meth:`_query.Query.set_label_style` method *only* applies
+ the output of :attr:`_query.Query.statement`, and *not* to any of
+ the result-row invoking systems of :class:`_query.Query` itself,
+ e.g.
+ :meth:`_query.Query.first`, :meth:`_query.Query.all`, etc.
+ To execute
+ a query using :meth:`_query.Query.set_label_style`, invoke the
+ :attr:`_query.Query.statement` using :meth:`.Session.execute`::
+
+ result = session.execute(
+ query
+ .set_label_style(LABEL_STYLE_TABLENAME_PLUS_COL)
+ .statement
+ )
+
+ .. versionadded:: 1.4
+
+
+ .. seealso::
+
+ :meth:`_sql.Select.set_label_style` - v2 equivalent method.
+
+ """ # noqa
+ if self._label_style is not style:
+ self = self._generate()
+ self._label_style = style
+ return self
+
+ @_generative
+ def enable_assertions(self, value: bool) -> Self:
+ """Control whether assertions are generated.
+
+ When set to False, the returned Query will
+ not assert its state before certain operations,
+ including that LIMIT/OFFSET has not been applied
+ when filter() is called, no criterion exists
+ when get() is called, and no "from_statement()"
+ exists when filter()/order_by()/group_by() etc.
+ is called. This more permissive mode is used by
+ custom Query subclasses to specify criterion or
+ other modifiers outside of the usual usage patterns.
+
+ Care should be taken to ensure that the usage
+ pattern is even possible. A statement applied
+ by from_statement() will override any criterion
+ set by filter() or order_by(), for example.
+
+ """
+ self._enable_assertions = value
+ return self
+
+ @property
+ def whereclause(self) -> Optional[ColumnElement[bool]]:
+ """A readonly attribute which returns the current WHERE criterion for
+ this Query.
+
+ This returned value is a SQL expression construct, or ``None`` if no
+ criterion has been established.
+
+ .. seealso::
+
+ :attr:`_sql.Select.whereclause` - v2 equivalent property.
+
+ """
+ return BooleanClauseList._construct_for_whereclause(
+ self._where_criteria
+ )
+
+ @_generative
+ def _with_current_path(self, path: PathRegistry) -> Self:
+ """indicate that this query applies to objects loaded
+ within a certain path.
+
+ Used by deferred loaders (see strategies.py) which transfer
+ query options from an originating query to a newly generated
+ query intended for the deferred load.
+
+ """
+ self._compile_options += {"_current_path": path}
+ return self
+
+ @_generative
+ def yield_per(self, count: int) -> Self:
+ r"""Yield only ``count`` rows at a time.
+
+ The purpose of this method is when fetching very large result sets
+ (> 10K rows), to batch results in sub-collections and yield them
+ out partially, so that the Python interpreter doesn't need to declare
+ very large areas of memory which is both time consuming and leads
+ to excessive memory use. The performance from fetching hundreds of
+ thousands of rows can often double when a suitable yield-per setting
+ (e.g. approximately 1000) is used, even with DBAPIs that buffer
+ rows (which are most).
+
+ As of SQLAlchemy 1.4, the :meth:`_orm.Query.yield_per` method is
+ equivalent to using the ``yield_per`` execution option at the ORM
+ level. See the section :ref:`orm_queryguide_yield_per` for further
+ background on this option.
+
+ .. seealso::
+
+ :ref:`orm_queryguide_yield_per`
+
+ """
+ self.load_options += {"_yield_per": count}
+ return self
+
+ @util.became_legacy_20(
+ ":meth:`_orm.Query.get`",
+ alternative="The method is now available as :meth:`_orm.Session.get`",
+ )
+ def get(self, ident: _PKIdentityArgument) -> Optional[Any]:
+ """Return an instance based on the given primary key identifier,
+ or ``None`` if not found.
+
+ E.g.::
+
+ my_user = session.query(User).get(5)
+
+ some_object = session.query(VersionedFoo).get((5, 10))
+
+ some_object = session.query(VersionedFoo).get(
+ {"id": 5, "version_id": 10})
+
+ :meth:`_query.Query.get` is special in that it provides direct
+ access to the identity map of the owning :class:`.Session`.
+ If the given primary key identifier is present
+ in the local identity map, the object is returned
+ directly from this collection and no SQL is emitted,
+ unless the object has been marked fully expired.
+ If not present,
+ a SELECT is performed in order to locate the object.
+
+ :meth:`_query.Query.get` also will perform a check if
+ the object is present in the identity map and
+ marked as expired - a SELECT
+ is emitted to refresh the object as well as to
+ ensure that the row is still present.
+ If not, :class:`~sqlalchemy.orm.exc.ObjectDeletedError` is raised.
+
+ :meth:`_query.Query.get` is only used to return a single
+ mapped instance, not multiple instances or
+ individual column constructs, and strictly
+ on a single primary key value. The originating
+ :class:`_query.Query` must be constructed in this way,
+ i.e. against a single mapped entity,
+ with no additional filtering criterion. Loading
+ options via :meth:`_query.Query.options` may be applied
+ however, and will be used if the object is not
+ yet locally present.
+
+ :param ident: A scalar, tuple, or dictionary representing the
+ primary key. For a composite (e.g. multiple column) primary key,
+ a tuple or dictionary should be passed.
+
+ For a single-column primary key, the scalar calling form is typically
+ the most expedient. If the primary key of a row is the value "5",
+ the call looks like::
+
+ my_object = query.get(5)
+
+ The tuple form contains primary key values typically in
+ the order in which they correspond to the mapped
+ :class:`_schema.Table`
+ object's primary key columns, or if the
+ :paramref:`_orm.Mapper.primary_key` configuration parameter were
+ used, in
+ the order used for that parameter. For example, if the primary key
+ of a row is represented by the integer
+ digits "5, 10" the call would look like::
+
+ my_object = query.get((5, 10))
+
+ The dictionary form should include as keys the mapped attribute names
+ corresponding to each element of the primary key. If the mapped class
+ has the attributes ``id``, ``version_id`` as the attributes which
+ store the object's primary key value, the call would look like::
+
+ my_object = query.get({"id": 5, "version_id": 10})
+
+ .. versionadded:: 1.3 the :meth:`_query.Query.get`
+ method now optionally
+ accepts a dictionary of attribute names to values in order to
+ indicate a primary key identifier.
+
+
+ :return: The object instance, or ``None``.
+
+ """
+ self._no_criterion_assertion("get", order_by=False, distinct=False)
+
+ # we still implement _get_impl() so that baked query can override
+ # it
+ return self._get_impl(ident, loading.load_on_pk_identity)
+
+ def _get_impl(
+ self,
+ primary_key_identity: _PKIdentityArgument,
+ db_load_fn: Callable[..., Any],
+ identity_token: Optional[Any] = None,
+ ) -> Optional[Any]:
+ mapper = self._only_full_mapper_zero("get")
+ return self.session._get_impl(
+ mapper,
+ primary_key_identity,
+ db_load_fn,
+ populate_existing=self.load_options._populate_existing,
+ with_for_update=self._for_update_arg,
+ options=self._with_options,
+ identity_token=identity_token,
+ execution_options=self._execution_options,
+ )
+
+ @property
+ def lazy_loaded_from(self) -> Optional[InstanceState[Any]]:
+ """An :class:`.InstanceState` that is using this :class:`_query.Query`
+ for a lazy load operation.
+
+ .. deprecated:: 1.4 This attribute should be viewed via the
+ :attr:`.ORMExecuteState.lazy_loaded_from` attribute, within
+ the context of the :meth:`.SessionEvents.do_orm_execute`
+ event.
+
+ .. seealso::
+
+ :attr:`.ORMExecuteState.lazy_loaded_from`
+
+ """
+ return self.load_options._lazy_loaded_from # type: ignore
+
+ @property
+ def _current_path(self) -> PathRegistry:
+ return self._compile_options._current_path # type: ignore
+
+ @_generative
+ def correlate(
+ self,
+ *fromclauses: Union[Literal[None, False], _FromClauseArgument],
+ ) -> Self:
+ """Return a :class:`.Query` construct which will correlate the given
+ FROM clauses to that of an enclosing :class:`.Query` or
+ :func:`~.expression.select`.
+
+ The method here accepts mapped classes, :func:`.aliased` constructs,
+ and :class:`_orm.Mapper` constructs as arguments, which are resolved
+ into expression constructs, in addition to appropriate expression
+ constructs.
+
+ The correlation arguments are ultimately passed to
+ :meth:`_expression.Select.correlate`
+ after coercion to expression constructs.
+
+ The correlation arguments take effect in such cases
+ as when :meth:`_query.Query.from_self` is used, or when
+ a subquery as returned by :meth:`_query.Query.subquery` is
+ embedded in another :func:`_expression.select` construct.
+
+ .. seealso::
+
+ :meth:`_sql.Select.correlate` - v2 equivalent method.
+
+ """
+
+ self._auto_correlate = False
+ if fromclauses and fromclauses[0] in {None, False}:
+ self._correlate = ()
+ else:
+ self._correlate = self._correlate + tuple(
+ coercions.expect(roles.FromClauseRole, f) for f in fromclauses
+ )
+ return self
+
+ @_generative
+ def autoflush(self, setting: bool) -> Self:
+ """Return a Query with a specific 'autoflush' setting.
+
+ As of SQLAlchemy 1.4, the :meth:`_orm.Query.autoflush` method
+ is equivalent to using the ``autoflush`` execution option at the
+ ORM level. See the section :ref:`orm_queryguide_autoflush` for
+ further background on this option.
+
+ """
+ self.load_options += {"_autoflush": setting}
+ return self
+
+ @_generative
+ def populate_existing(self) -> Self:
+ """Return a :class:`_query.Query`
+ that will expire and refresh all instances
+ as they are loaded, or reused from the current :class:`.Session`.
+
+ As of SQLAlchemy 1.4, the :meth:`_orm.Query.populate_existing` method
+ is equivalent to using the ``populate_existing`` execution option at
+ the ORM level. See the section :ref:`orm_queryguide_populate_existing`
+ for further background on this option.
+
+ """
+ self.load_options += {"_populate_existing": True}
+ return self
+
+ @_generative
+ def _with_invoke_all_eagers(self, value: bool) -> Self:
+ """Set the 'invoke all eagers' flag which causes joined- and
+ subquery loaders to traverse into already-loaded related objects
+ and collections.
+
+ Default is that of :attr:`_query.Query._invoke_all_eagers`.
+
+ """
+ self.load_options += {"_invoke_all_eagers": value}
+ return self
+
+ @util.became_legacy_20(
+ ":meth:`_orm.Query.with_parent`",
+ alternative="Use the :func:`_orm.with_parent` standalone construct.",
+ )
+ @util.preload_module("sqlalchemy.orm.relationships")
+ def with_parent(
+ self,
+ instance: object,
+ property: Optional[ # noqa: A002
+ attributes.QueryableAttribute[Any]
+ ] = None,
+ from_entity: Optional[_ExternalEntityType[Any]] = None,
+ ) -> Self:
+ """Add filtering criterion that relates the given instance
+ to a child object or collection, using its attribute state
+ as well as an established :func:`_orm.relationship()`
+ configuration.
+
+ The method uses the :func:`.with_parent` function to generate
+ the clause, the result of which is passed to
+ :meth:`_query.Query.filter`.
+
+ Parameters are the same as :func:`.with_parent`, with the exception
+ that the given property can be None, in which case a search is
+ performed against this :class:`_query.Query` object's target mapper.
+
+ :param instance:
+ An instance which has some :func:`_orm.relationship`.
+
+ :param property:
+ Class bound attribute which indicates
+ what relationship from the instance should be used to reconcile the
+ parent/child relationship.
+
+ :param from_entity:
+ Entity in which to consider as the left side. This defaults to the
+ "zero" entity of the :class:`_query.Query` itself.
+
+ """
+ relationships = util.preloaded.orm_relationships
+
+ if from_entity:
+ entity_zero = inspect(from_entity)
+ else:
+ entity_zero = _legacy_filter_by_entity_zero(self)
+ if property is None:
+ # TODO: deprecate, property has to be supplied
+ mapper = object_mapper(instance)
+
+ for prop in mapper.iterate_properties:
+ if (
+ isinstance(prop, relationships.RelationshipProperty)
+ and prop.mapper is entity_zero.mapper # type: ignore
+ ):
+ property = prop # type: ignore # noqa: A001
+ break
+ else:
+ raise sa_exc.InvalidRequestError(
+ "Could not locate a property which relates instances "
+ "of class '%s' to instances of class '%s'"
+ % (
+ entity_zero.mapper.class_.__name__, # type: ignore
+ instance.__class__.__name__,
+ )
+ )
+
+ return self.filter(
+ with_parent(
+ instance,
+ property, # type: ignore
+ entity_zero.entity, # type: ignore
+ )
+ )
+
+ @_generative
+ def add_entity(
+ self,
+ entity: _EntityType[Any],
+ alias: Optional[Union[Alias, Subquery]] = None,
+ ) -> Query[Any]:
+ """add a mapped entity to the list of result columns
+ to be returned.
+
+ .. seealso::
+
+ :meth:`_sql.Select.add_columns` - v2 comparable method.
+ """
+
+ if alias is not None:
+ # TODO: deprecate
+ entity = AliasedClass(entity, alias)
+
+ self._raw_columns = list(self._raw_columns)
+
+ self._raw_columns.append(
+ coercions.expect(
+ roles.ColumnsClauseRole, entity, apply_propagate_attrs=self
+ )
+ )
+ return self
+
+ @_generative
+ def with_session(self, session: Session) -> Self:
+ """Return a :class:`_query.Query` that will use the given
+ :class:`.Session`.
+
+ While the :class:`_query.Query`
+ object is normally instantiated using the
+ :meth:`.Session.query` method, it is legal to build the
+ :class:`_query.Query`
+ directly without necessarily using a :class:`.Session`. Such a
+ :class:`_query.Query` object, or any :class:`_query.Query`
+ already associated
+ with a different :class:`.Session`, can produce a new
+ :class:`_query.Query`
+ object associated with a target session using this method::
+
+ from sqlalchemy.orm import Query
+
+ query = Query([MyClass]).filter(MyClass.id == 5)
+
+ result = query.with_session(my_session).one()
+
+ """
+
+ self.session = session
+ return self
+
+ def _legacy_from_self(
+ self, *entities: _ColumnsClauseArgument[Any]
+ ) -> Self:
+ # used for query.count() as well as for the same
+ # function in BakedQuery, as well as some old tests in test_baked.py.
+
+ fromclause = (
+ self.set_label_style(LABEL_STYLE_TABLENAME_PLUS_COL)
+ .correlate(None)
+ .subquery()
+ ._anonymous_fromclause()
+ )
+
+ q = self._from_selectable(fromclause)
+
+ if entities:
+ q._set_entities(entities)
+ return q
+
+ @_generative
+ def _set_enable_single_crit(self, val: bool) -> Self:
+ self._compile_options += {"_enable_single_crit": val}
+ return self
+
+ @_generative
+ def _from_selectable(
+ self, fromclause: FromClause, set_entity_from: bool = True
+ ) -> Self:
+ for attr in (
+ "_where_criteria",
+ "_order_by_clauses",
+ "_group_by_clauses",
+ "_limit_clause",
+ "_offset_clause",
+ "_last_joined_entity",
+ "_setup_joins",
+ "_memoized_select_entities",
+ "_distinct",
+ "_distinct_on",
+ "_having_criteria",
+ "_prefixes",
+ "_suffixes",
+ ):
+ self.__dict__.pop(attr, None)
+ self._set_select_from([fromclause], set_entity_from)
+ self._compile_options += {
+ "_enable_single_crit": False,
+ }
+
+ return self
+
+ @util.deprecated(
+ "1.4",
+ ":meth:`_query.Query.values` "
+ "is deprecated and will be removed in a "
+ "future release. Please use :meth:`_query.Query.with_entities`",
+ )
+ def values(self, *columns: _ColumnsClauseArgument[Any]) -> Iterable[Any]:
+ """Return an iterator yielding result tuples corresponding
+ to the given list of columns
+
+ """
+ return self._values_no_warn(*columns)
+
+ _values = values
+
+ def _values_no_warn(
+ self, *columns: _ColumnsClauseArgument[Any]
+ ) -> Iterable[Any]:
+ if not columns:
+ return iter(())
+ q = self._clone().enable_eagerloads(False)
+ q._set_entities(columns)
+ if not q.load_options._yield_per:
+ q.load_options += {"_yield_per": 10}
+ return iter(q)
+
+ @util.deprecated(
+ "1.4",
+ ":meth:`_query.Query.value` "
+ "is deprecated and will be removed in a "
+ "future release. Please use :meth:`_query.Query.with_entities` "
+ "in combination with :meth:`_query.Query.scalar`",
+ )
+ def value(self, column: _ColumnExpressionArgument[Any]) -> Any:
+ """Return a scalar result corresponding to the given
+ column expression.
+
+ """
+ try:
+ return next(self._values_no_warn(column))[0] # type: ignore
+ except StopIteration:
+ return None
+
+ @overload
+ def with_entities(self, _entity: _EntityType[_O]) -> Query[_O]: ...
+
+ @overload
+ def with_entities(
+ self,
+ _colexpr: roles.TypedColumnsClauseRole[_T],
+ ) -> RowReturningQuery[Tuple[_T]]: ...
+
+ # START OVERLOADED FUNCTIONS self.with_entities RowReturningQuery 2-8
+
+ # code within this block is **programmatically,
+ # statically generated** by tools/generate_tuple_map_overloads.py
+
+ @overload
+ def with_entities(
+ self, __ent0: _TCCA[_T0], __ent1: _TCCA[_T1]
+ ) -> RowReturningQuery[Tuple[_T0, _T1]]: ...
+
+ @overload
+ def with_entities(
+ self, __ent0: _TCCA[_T0], __ent1: _TCCA[_T1], __ent2: _TCCA[_T2]
+ ) -> RowReturningQuery[Tuple[_T0, _T1, _T2]]: ...
+
+ @overload
+ def with_entities(
+ self,
+ __ent0: _TCCA[_T0],
+ __ent1: _TCCA[_T1],
+ __ent2: _TCCA[_T2],
+ __ent3: _TCCA[_T3],
+ ) -> RowReturningQuery[Tuple[_T0, _T1, _T2, _T3]]: ...
+
+ @overload
+ def with_entities(
+ self,
+ __ent0: _TCCA[_T0],
+ __ent1: _TCCA[_T1],
+ __ent2: _TCCA[_T2],
+ __ent3: _TCCA[_T3],
+ __ent4: _TCCA[_T4],
+ ) -> RowReturningQuery[Tuple[_T0, _T1, _T2, _T3, _T4]]: ...
+
+ @overload
+ def with_entities(
+ self,
+ __ent0: _TCCA[_T0],
+ __ent1: _TCCA[_T1],
+ __ent2: _TCCA[_T2],
+ __ent3: _TCCA[_T3],
+ __ent4: _TCCA[_T4],
+ __ent5: _TCCA[_T5],
+ ) -> RowReturningQuery[Tuple[_T0, _T1, _T2, _T3, _T4, _T5]]: ...
+
+ @overload
+ def with_entities(
+ self,
+ __ent0: _TCCA[_T0],
+ __ent1: _TCCA[_T1],
+ __ent2: _TCCA[_T2],
+ __ent3: _TCCA[_T3],
+ __ent4: _TCCA[_T4],
+ __ent5: _TCCA[_T5],
+ __ent6: _TCCA[_T6],
+ ) -> RowReturningQuery[Tuple[_T0, _T1, _T2, _T3, _T4, _T5, _T6]]: ...
+
+ @overload
+ def with_entities(
+ self,
+ __ent0: _TCCA[_T0],
+ __ent1: _TCCA[_T1],
+ __ent2: _TCCA[_T2],
+ __ent3: _TCCA[_T3],
+ __ent4: _TCCA[_T4],
+ __ent5: _TCCA[_T5],
+ __ent6: _TCCA[_T6],
+ __ent7: _TCCA[_T7],
+ ) -> RowReturningQuery[Tuple[_T0, _T1, _T2, _T3, _T4, _T5, _T6, _T7]]: ...
+
+ # END OVERLOADED FUNCTIONS self.with_entities
+
+ @overload
+ def with_entities(
+ self, *entities: _ColumnsClauseArgument[Any]
+ ) -> Query[Any]: ...
+
+ @_generative
+ def with_entities(
+ self, *entities: _ColumnsClauseArgument[Any], **__kw: Any
+ ) -> Query[Any]:
+ r"""Return a new :class:`_query.Query`
+ replacing the SELECT list with the
+ given entities.
+
+ e.g.::
+
+ # Users, filtered on some arbitrary criterion
+ # and then ordered by related email address
+ q = session.query(User).\
+ join(User.address).\
+ filter(User.name.like('%ed%')).\
+ order_by(Address.email)
+
+ # given *only* User.id==5, Address.email, and 'q', what
+ # would the *next* User in the result be ?
+ subq = q.with_entities(Address.email).\
+ order_by(None).\
+ filter(User.id==5).\
+ subquery()
+ q = q.join((subq, subq.c.email < Address.email)).\
+ limit(1)
+
+ .. seealso::
+
+ :meth:`_sql.Select.with_only_columns` - v2 comparable method.
+ """
+ if __kw:
+ raise _no_kw()
+
+ # Query has all the same fields as Select for this operation
+ # this could in theory be based on a protocol but not sure if it's
+ # worth it
+ _MemoizedSelectEntities._generate_for_statement(self) # type: ignore
+ self._set_entities(entities)
+ return self
+
+ @_generative
+ def add_columns(
+ self, *column: _ColumnExpressionArgument[Any]
+ ) -> Query[Any]:
+ """Add one or more column expressions to the list
+ of result columns to be returned.
+
+ .. seealso::
+
+ :meth:`_sql.Select.add_columns` - v2 comparable method.
+ """
+
+ self._raw_columns = list(self._raw_columns)
+
+ self._raw_columns.extend(
+ coercions.expect(
+ roles.ColumnsClauseRole,
+ c,
+ apply_propagate_attrs=self,
+ post_inspect=True,
+ )
+ for c in column
+ )
+ return self
+
+ @util.deprecated(
+ "1.4",
+ ":meth:`_query.Query.add_column` "
+ "is deprecated and will be removed in a "
+ "future release. Please use :meth:`_query.Query.add_columns`",
+ )
+ def add_column(self, column: _ColumnExpressionArgument[Any]) -> Query[Any]:
+ """Add a column expression to the list of result columns to be
+ returned.
+
+ """
+ return self.add_columns(column)
+
+ @_generative
+ def options(self, *args: ExecutableOption) -> Self:
+ """Return a new :class:`_query.Query` object,
+ applying the given list of
+ mapper options.
+
+ Most supplied options regard changing how column- and
+ relationship-mapped attributes are loaded.
+
+ .. seealso::
+
+ :ref:`loading_columns`
+
+ :ref:`relationship_loader_options`
+
+ """
+
+ opts = tuple(util.flatten_iterator(args))
+ if self._compile_options._current_path:
+ # opting for lower method overhead for the checks
+ for opt in opts:
+ if not opt._is_core and opt._is_legacy_option: # type: ignore
+ opt.process_query_conditionally(self) # type: ignore
+ else:
+ for opt in opts:
+ if not opt._is_core and opt._is_legacy_option: # type: ignore
+ opt.process_query(self) # type: ignore
+
+ self._with_options += opts
+ return self
+
+ def with_transformation(
+ self, fn: Callable[[Query[Any]], Query[Any]]
+ ) -> Query[Any]:
+ """Return a new :class:`_query.Query` object transformed by
+ the given function.
+
+ E.g.::
+
+ def filter_something(criterion):
+ def transform(q):
+ return q.filter(criterion)
+ return transform
+
+ q = q.with_transformation(filter_something(x==5))
+
+ This allows ad-hoc recipes to be created for :class:`_query.Query`
+ objects.
+
+ """
+ return fn(self)
+
+ def get_execution_options(self) -> _ImmutableExecuteOptions:
+ """Get the non-SQL options which will take effect during execution.
+
+ .. versionadded:: 1.3
+
+ .. seealso::
+
+ :meth:`_query.Query.execution_options`
+
+ :meth:`_sql.Select.get_execution_options` - v2 comparable method.
+
+ """
+ return self._execution_options
+
+ @overload
+ def execution_options(
+ self,
+ *,
+ compiled_cache: Optional[CompiledCacheType] = ...,
+ logging_token: str = ...,
+ isolation_level: IsolationLevel = ...,
+ no_parameters: bool = False,
+ stream_results: bool = False,
+ max_row_buffer: int = ...,
+ yield_per: int = ...,
+ insertmanyvalues_page_size: int = ...,
+ schema_translate_map: Optional[SchemaTranslateMapType] = ...,
+ populate_existing: bool = False,
+ autoflush: bool = False,
+ preserve_rowcount: bool = False,
+ **opt: Any,
+ ) -> Self: ...
+
+ @overload
+ def execution_options(self, **opt: Any) -> Self: ...
+
+ @_generative
+ def execution_options(self, **kwargs: Any) -> Self:
+ """Set non-SQL options which take effect during execution.
+
+ Options allowed here include all of those accepted by
+ :meth:`_engine.Connection.execution_options`, as well as a series
+ of ORM specific options:
+
+ ``populate_existing=True`` - equivalent to using
+ :meth:`_orm.Query.populate_existing`
+
+ ``autoflush=True|False`` - equivalent to using
+ :meth:`_orm.Query.autoflush`
+
+ ``yield_per=<value>`` - equivalent to using
+ :meth:`_orm.Query.yield_per`
+
+ Note that the ``stream_results`` execution option is enabled
+ automatically if the :meth:`~sqlalchemy.orm.query.Query.yield_per()`
+ method or execution option is used.
+
+ .. versionadded:: 1.4 - added ORM options to
+ :meth:`_orm.Query.execution_options`
+
+ The execution options may also be specified on a per execution basis
+ when using :term:`2.0 style` queries via the
+ :paramref:`_orm.Session.execution_options` parameter.
+
+ .. warning:: The
+ :paramref:`_engine.Connection.execution_options.stream_results`
+ parameter should not be used at the level of individual ORM
+ statement executions, as the :class:`_orm.Session` will not track
+ objects from different schema translate maps within a single
+ session. For multiple schema translate maps within the scope of a
+ single :class:`_orm.Session`, see :ref:`examples_sharding`.
+
+
+ .. seealso::
+
+ :ref:`engine_stream_results`
+
+ :meth:`_query.Query.get_execution_options`
+
+ :meth:`_sql.Select.execution_options` - v2 equivalent method.
+
+ """
+ self._execution_options = self._execution_options.union(kwargs)
+ return self
+
+ @_generative
+ def with_for_update(
+ self,
+ *,
+ nowait: bool = False,
+ read: bool = False,
+ of: Optional[_ForUpdateOfArgument] = None,
+ skip_locked: bool = False,
+ key_share: bool = False,
+ ) -> Self:
+ """return a new :class:`_query.Query`
+ with the specified options for the
+ ``FOR UPDATE`` clause.
+
+ The behavior of this method is identical to that of
+ :meth:`_expression.GenerativeSelect.with_for_update`.
+ When called with no arguments,
+ the resulting ``SELECT`` statement will have a ``FOR UPDATE`` clause
+ appended. When additional arguments are specified, backend-specific
+ options such as ``FOR UPDATE NOWAIT`` or ``LOCK IN SHARE MODE``
+ can take effect.
+
+ E.g.::
+
+ q = sess.query(User).populate_existing().with_for_update(nowait=True, of=User)
+
+ The above query on a PostgreSQL backend will render like::
+
+ SELECT users.id AS users_id FROM users FOR UPDATE OF users NOWAIT
+
+ .. warning::
+
+ Using ``with_for_update`` in the context of eager loading
+ relationships is not officially supported or recommended by
+ SQLAlchemy and may not work with certain queries on various
+ database backends. When ``with_for_update`` is successfully used
+ with a query that involves :func:`_orm.joinedload`, SQLAlchemy will
+ attempt to emit SQL that locks all involved tables.
+
+ .. note:: It is generally a good idea to combine the use of the
+ :meth:`_orm.Query.populate_existing` method when using the
+ :meth:`_orm.Query.with_for_update` method. The purpose of
+ :meth:`_orm.Query.populate_existing` is to force all the data read
+ from the SELECT to be populated into the ORM objects returned,
+ even if these objects are already in the :term:`identity map`.
+
+ .. seealso::
+
+ :meth:`_expression.GenerativeSelect.with_for_update`
+ - Core level method with
+ full argument and behavioral description.
+
+ :meth:`_orm.Query.populate_existing` - overwrites attributes of
+ objects already loaded in the identity map.
+
+ """ # noqa: E501
+
+ self._for_update_arg = ForUpdateArg(
+ read=read,
+ nowait=nowait,
+ of=of,
+ skip_locked=skip_locked,
+ key_share=key_share,
+ )
+ return self
+
+ @_generative
+ def params(
+ self, __params: Optional[Dict[str, Any]] = None, **kw: Any
+ ) -> Self:
+ r"""Add values for bind parameters which may have been
+ specified in filter().
+
+ Parameters may be specified using \**kwargs, or optionally a single
+ dictionary as the first positional argument. The reason for both is
+ that \**kwargs is convenient, however some parameter dictionaries
+ contain unicode keys in which case \**kwargs cannot be used.
+
+ """
+ if __params:
+ kw.update(__params)
+ self._params = self._params.union(kw)
+ return self
+
+ def where(self, *criterion: _ColumnExpressionArgument[bool]) -> Self:
+ """A synonym for :meth:`.Query.filter`.
+
+ .. versionadded:: 1.4
+
+ .. seealso::
+
+ :meth:`_sql.Select.where` - v2 equivalent method.
+
+ """
+ return self.filter(*criterion)
+
+ @_generative
+ @_assertions(_no_statement_condition, _no_limit_offset)
+ def filter(self, *criterion: _ColumnExpressionArgument[bool]) -> Self:
+ r"""Apply the given filtering criterion to a copy
+ of this :class:`_query.Query`, using SQL expressions.
+
+ e.g.::
+
+ session.query(MyClass).filter(MyClass.name == 'some name')
+
+ Multiple criteria may be specified as comma separated; the effect
+ is that they will be joined together using the :func:`.and_`
+ function::
+
+ session.query(MyClass).\
+ filter(MyClass.name == 'some name', MyClass.id > 5)
+
+ The criterion is any SQL expression object applicable to the
+ WHERE clause of a select. String expressions are coerced
+ into SQL expression constructs via the :func:`_expression.text`
+ construct.
+
+ .. seealso::
+
+ :meth:`_query.Query.filter_by` - filter on keyword expressions.
+
+ :meth:`_sql.Select.where` - v2 equivalent method.
+
+ """
+ for crit in list(criterion):
+ crit = coercions.expect(
+ roles.WhereHavingRole, crit, apply_propagate_attrs=self
+ )
+
+ self._where_criteria += (crit,)
+ return self
+
+ @util.memoized_property
+ def _last_joined_entity(
+ self,
+ ) -> Optional[Union[_InternalEntityType[Any], _JoinTargetElement]]:
+ if self._setup_joins:
+ return _determine_last_joined_entity(
+ self._setup_joins,
+ )
+ else:
+ return None
+
+ def _filter_by_zero(self) -> Any:
+ """for the filter_by() method, return the target entity for which
+ we will attempt to derive an expression from based on string name.
+
+ """
+
+ if self._setup_joins:
+ _last_joined_entity = self._last_joined_entity
+ if _last_joined_entity is not None:
+ return _last_joined_entity
+
+ # discussion related to #7239
+ # special check determines if we should try to derive attributes
+ # for filter_by() from the "from object", i.e., if the user
+ # called query.select_from(some selectable).filter_by(some_attr=value).
+ # We don't want to do that in the case that methods like
+ # from_self(), select_entity_from(), or a set op like union() were
+ # called; while these methods also place a
+ # selectable in the _from_obj collection, they also set up
+ # the _set_base_alias boolean which turns on the whole "adapt the
+ # entity to this selectable" thing, meaning the query still continues
+ # to construct itself in terms of the lead entity that was passed
+ # to query(), e.g. query(User).from_self() is still in terms of User,
+ # and not the subquery that from_self() created. This feature of
+ # "implicitly adapt all occurrences of entity X to some arbitrary
+ # subquery" is the main thing I am trying to do away with in 2.0 as
+ # users should now used aliased() for that, but I can't entirely get
+ # rid of it due to query.union() and other set ops relying upon it.
+ #
+ # compare this to the base Select()._filter_by_zero() which can
+ # just return self._from_obj[0] if present, because there is no
+ # "_set_base_alias" feature.
+ #
+ # IOW, this conditional essentially detects if
+ # "select_from(some_selectable)" has been called, as opposed to
+ # "select_entity_from()", "from_self()"
+ # or "union() / some_set_op()".
+ if self._from_obj and not self._compile_options._set_base_alias:
+ return self._from_obj[0]
+
+ return self._raw_columns[0]
+
+ def filter_by(self, **kwargs: Any) -> Self:
+ r"""Apply the given filtering criterion to a copy
+ of this :class:`_query.Query`, using keyword expressions.
+
+ e.g.::
+
+ session.query(MyClass).filter_by(name = 'some name')
+
+ Multiple criteria may be specified as comma separated; the effect
+ is that they will be joined together using the :func:`.and_`
+ function::
+
+ session.query(MyClass).\
+ filter_by(name = 'some name', id = 5)
+
+ The keyword expressions are extracted from the primary
+ entity of the query, or the last entity that was the
+ target of a call to :meth:`_query.Query.join`.
+
+ .. seealso::
+
+ :meth:`_query.Query.filter` - filter on SQL expressions.
+
+ :meth:`_sql.Select.filter_by` - v2 comparable method.
+
+ """
+ from_entity = self._filter_by_zero()
+
+ clauses = [
+ _entity_namespace_key(from_entity, key) == value
+ for key, value in kwargs.items()
+ ]
+ return self.filter(*clauses)
+
+ @_generative
+ def order_by(
+ self,
+ __first: Union[
+ Literal[None, False, _NoArg.NO_ARG],
+ _ColumnExpressionOrStrLabelArgument[Any],
+ ] = _NoArg.NO_ARG,
+ *clauses: _ColumnExpressionOrStrLabelArgument[Any],
+ ) -> Self:
+ """Apply one or more ORDER BY criteria to the query and return
+ the newly resulting :class:`_query.Query`.
+
+ e.g.::
+
+ q = session.query(Entity).order_by(Entity.id, Entity.name)
+
+ Calling this method multiple times is equivalent to calling it once
+ with all the clauses concatenated. All existing ORDER BY criteria may
+ be cancelled by passing ``None`` by itself. New ORDER BY criteria may
+ then be added by invoking :meth:`_orm.Query.order_by` again, e.g.::
+
+ # will erase all ORDER BY and ORDER BY new_col alone
+ q = q.order_by(None).order_by(new_col)
+
+ .. seealso::
+
+ These sections describe ORDER BY in terms of :term:`2.0 style`
+ invocation but apply to :class:`_orm.Query` as well:
+
+ :ref:`tutorial_order_by` - in the :ref:`unified_tutorial`
+
+ :ref:`tutorial_order_by_label` - in the :ref:`unified_tutorial`
+
+ :meth:`_sql.Select.order_by` - v2 equivalent method.
+
+ """
+
+ for assertion in (self._no_statement_condition, self._no_limit_offset):
+ assertion("order_by")
+
+ if not clauses and (__first is None or __first is False):
+ self._order_by_clauses = ()
+ elif __first is not _NoArg.NO_ARG:
+ criterion = tuple(
+ coercions.expect(roles.OrderByRole, clause)
+ for clause in (__first,) + clauses
+ )
+ self._order_by_clauses += criterion
+
+ return self
+
+ @_generative
+ def group_by(
+ self,
+ __first: Union[
+ Literal[None, False, _NoArg.NO_ARG],
+ _ColumnExpressionOrStrLabelArgument[Any],
+ ] = _NoArg.NO_ARG,
+ *clauses: _ColumnExpressionOrStrLabelArgument[Any],
+ ) -> Self:
+ """Apply one or more GROUP BY criterion to the query and return
+ the newly resulting :class:`_query.Query`.
+
+ All existing GROUP BY settings can be suppressed by
+ passing ``None`` - this will suppress any GROUP BY configured
+ on mappers as well.
+
+ .. seealso::
+
+ These sections describe GROUP BY in terms of :term:`2.0 style`
+ invocation but apply to :class:`_orm.Query` as well:
+
+ :ref:`tutorial_group_by_w_aggregates` - in the
+ :ref:`unified_tutorial`
+
+ :ref:`tutorial_order_by_label` - in the :ref:`unified_tutorial`
+
+ :meth:`_sql.Select.group_by` - v2 equivalent method.
+
+ """
+
+ for assertion in (self._no_statement_condition, self._no_limit_offset):
+ assertion("group_by")
+
+ if not clauses and (__first is None or __first is False):
+ self._group_by_clauses = ()
+ elif __first is not _NoArg.NO_ARG:
+ criterion = tuple(
+ coercions.expect(roles.GroupByRole, clause)
+ for clause in (__first,) + clauses
+ )
+ self._group_by_clauses += criterion
+ return self
+
+ @_generative
+ @_assertions(_no_statement_condition, _no_limit_offset)
+ def having(self, *having: _ColumnExpressionArgument[bool]) -> Self:
+ r"""Apply a HAVING criterion to the query and return the
+ newly resulting :class:`_query.Query`.
+
+ :meth:`_query.Query.having` is used in conjunction with
+ :meth:`_query.Query.group_by`.
+
+ HAVING criterion makes it possible to use filters on aggregate
+ functions like COUNT, SUM, AVG, MAX, and MIN, eg.::
+
+ q = session.query(User.id).\
+ join(User.addresses).\
+ group_by(User.id).\
+ having(func.count(Address.id) > 2)
+
+ .. seealso::
+
+ :meth:`_sql.Select.having` - v2 equivalent method.
+
+ """
+
+ for criterion in having:
+ having_criteria = coercions.expect(
+ roles.WhereHavingRole, criterion
+ )
+ self._having_criteria += (having_criteria,)
+ return self
+
+ def _set_op(self, expr_fn: Any, *q: Query[Any]) -> Self:
+ list_of_queries = (self,) + q
+ return self._from_selectable(expr_fn(*(list_of_queries)).subquery())
+
+ def union(self, *q: Query[Any]) -> Self:
+ """Produce a UNION of this Query against one or more queries.
+
+ e.g.::
+
+ q1 = sess.query(SomeClass).filter(SomeClass.foo=='bar')
+ q2 = sess.query(SomeClass).filter(SomeClass.bar=='foo')
+
+ q3 = q1.union(q2)
+
+ The method accepts multiple Query objects so as to control
+ the level of nesting. A series of ``union()`` calls such as::
+
+ x.union(y).union(z).all()
+
+ will nest on each ``union()``, and produces::
+
+ SELECT * FROM (SELECT * FROM (SELECT * FROM X UNION
+ SELECT * FROM y) UNION SELECT * FROM Z)
+
+ Whereas::
+
+ x.union(y, z).all()
+
+ produces::
+
+ SELECT * FROM (SELECT * FROM X UNION SELECT * FROM y UNION
+ SELECT * FROM Z)
+
+ Note that many database backends do not allow ORDER BY to
+ be rendered on a query called within UNION, EXCEPT, etc.
+ To disable all ORDER BY clauses including those configured
+ on mappers, issue ``query.order_by(None)`` - the resulting
+ :class:`_query.Query` object will not render ORDER BY within
+ its SELECT statement.
+
+ .. seealso::
+
+ :meth:`_sql.Select.union` - v2 equivalent method.
+
+ """
+ return self._set_op(expression.union, *q)
+
+ def union_all(self, *q: Query[Any]) -> Self:
+ """Produce a UNION ALL of this Query against one or more queries.
+
+ Works the same way as :meth:`~sqlalchemy.orm.query.Query.union`. See
+ that method for usage examples.
+
+ .. seealso::
+
+ :meth:`_sql.Select.union_all` - v2 equivalent method.
+
+ """
+ return self._set_op(expression.union_all, *q)
+
+ def intersect(self, *q: Query[Any]) -> Self:
+ """Produce an INTERSECT of this Query against one or more queries.
+
+ Works the same way as :meth:`~sqlalchemy.orm.query.Query.union`. See
+ that method for usage examples.
+
+ .. seealso::
+
+ :meth:`_sql.Select.intersect` - v2 equivalent method.
+
+ """
+ return self._set_op(expression.intersect, *q)
+
+ def intersect_all(self, *q: Query[Any]) -> Self:
+ """Produce an INTERSECT ALL of this Query against one or more queries.
+
+ Works the same way as :meth:`~sqlalchemy.orm.query.Query.union`. See
+ that method for usage examples.
+
+ .. seealso::
+
+ :meth:`_sql.Select.intersect_all` - v2 equivalent method.
+
+ """
+ return self._set_op(expression.intersect_all, *q)
+
+ def except_(self, *q: Query[Any]) -> Self:
+ """Produce an EXCEPT of this Query against one or more queries.
+
+ Works the same way as :meth:`~sqlalchemy.orm.query.Query.union`. See
+ that method for usage examples.
+
+ .. seealso::
+
+ :meth:`_sql.Select.except_` - v2 equivalent method.
+
+ """
+ return self._set_op(expression.except_, *q)
+
+ def except_all(self, *q: Query[Any]) -> Self:
+ """Produce an EXCEPT ALL of this Query against one or more queries.
+
+ Works the same way as :meth:`~sqlalchemy.orm.query.Query.union`. See
+ that method for usage examples.
+
+ .. seealso::
+
+ :meth:`_sql.Select.except_all` - v2 equivalent method.
+
+ """
+ return self._set_op(expression.except_all, *q)
+
+ @_generative
+ @_assertions(_no_statement_condition, _no_limit_offset)
+ def join(
+ self,
+ target: _JoinTargetArgument,
+ onclause: Optional[_OnClauseArgument] = None,
+ *,
+ isouter: bool = False,
+ full: bool = False,
+ ) -> Self:
+ r"""Create a SQL JOIN against this :class:`_query.Query`
+ object's criterion
+ and apply generatively, returning the newly resulting
+ :class:`_query.Query`.
+
+ **Simple Relationship Joins**
+
+ Consider a mapping between two classes ``User`` and ``Address``,
+ with a relationship ``User.addresses`` representing a collection
+ of ``Address`` objects associated with each ``User``. The most
+ common usage of :meth:`_query.Query.join`
+ is to create a JOIN along this
+ relationship, using the ``User.addresses`` attribute as an indicator
+ for how this should occur::
+
+ q = session.query(User).join(User.addresses)
+
+ Where above, the call to :meth:`_query.Query.join` along
+ ``User.addresses`` will result in SQL approximately equivalent to::
+
+ SELECT user.id, user.name
+ FROM user JOIN address ON user.id = address.user_id
+
+ In the above example we refer to ``User.addresses`` as passed to
+ :meth:`_query.Query.join` as the "on clause", that is, it indicates
+ how the "ON" portion of the JOIN should be constructed.
+
+ To construct a chain of joins, multiple :meth:`_query.Query.join`
+ calls may be used. The relationship-bound attribute implies both
+ the left and right side of the join at once::
+
+ q = session.query(User).\
+ join(User.orders).\
+ join(Order.items).\
+ join(Item.keywords)
+
+ .. note:: as seen in the above example, **the order in which each
+ call to the join() method occurs is important**. Query would not,
+ for example, know how to join correctly if we were to specify
+ ``User``, then ``Item``, then ``Order``, in our chain of joins; in
+ such a case, depending on the arguments passed, it may raise an
+ error that it doesn't know how to join, or it may produce invalid
+ SQL in which case the database will raise an error. In correct
+ practice, the
+ :meth:`_query.Query.join` method is invoked in such a way that lines
+ up with how we would want the JOIN clauses in SQL to be
+ rendered, and each call should represent a clear link from what
+ precedes it.
+
+ **Joins to a Target Entity or Selectable**
+
+ A second form of :meth:`_query.Query.join` allows any mapped entity or
+ core selectable construct as a target. In this usage,
+ :meth:`_query.Query.join` will attempt to create a JOIN along the
+ natural foreign key relationship between two entities::
+
+ q = session.query(User).join(Address)
+
+ In the above calling form, :meth:`_query.Query.join` is called upon to
+ create the "on clause" automatically for us. This calling form will
+ ultimately raise an error if either there are no foreign keys between
+ the two entities, or if there are multiple foreign key linkages between
+ the target entity and the entity or entities already present on the
+ left side such that creating a join requires more information. Note
+ that when indicating a join to a target without any ON clause, ORM
+ configured relationships are not taken into account.
+
+ **Joins to a Target with an ON Clause**
+
+ The third calling form allows both the target entity as well
+ as the ON clause to be passed explicitly. A example that includes
+ a SQL expression as the ON clause is as follows::
+
+ q = session.query(User).join(Address, User.id==Address.user_id)
+
+ The above form may also use a relationship-bound attribute as the
+ ON clause as well::
+
+ q = session.query(User).join(Address, User.addresses)
+
+ The above syntax can be useful for the case where we wish
+ to join to an alias of a particular target entity. If we wanted
+ to join to ``Address`` twice, it could be achieved using two
+ aliases set up using the :func:`~sqlalchemy.orm.aliased` function::
+
+ a1 = aliased(Address)
+ a2 = aliased(Address)
+
+ q = session.query(User).\
+ join(a1, User.addresses).\
+ join(a2, User.addresses).\
+ filter(a1.email_address=='ed@foo.com').\
+ filter(a2.email_address=='ed@bar.com')
+
+ The relationship-bound calling form can also specify a target entity
+ using the :meth:`_orm.PropComparator.of_type` method; a query
+ equivalent to the one above would be::
+
+ a1 = aliased(Address)
+ a2 = aliased(Address)
+
+ q = session.query(User).\
+ join(User.addresses.of_type(a1)).\
+ join(User.addresses.of_type(a2)).\
+ filter(a1.email_address == 'ed@foo.com').\
+ filter(a2.email_address == 'ed@bar.com')
+
+ **Augmenting Built-in ON Clauses**
+
+ As a substitute for providing a full custom ON condition for an
+ existing relationship, the :meth:`_orm.PropComparator.and_` function
+ may be applied to a relationship attribute to augment additional
+ criteria into the ON clause; the additional criteria will be combined
+ with the default criteria using AND::
+
+ q = session.query(User).join(
+ User.addresses.and_(Address.email_address != 'foo@bar.com')
+ )
+
+ .. versionadded:: 1.4
+
+ **Joining to Tables and Subqueries**
+
+
+ The target of a join may also be any table or SELECT statement,
+ which may be related to a target entity or not. Use the
+ appropriate ``.subquery()`` method in order to make a subquery
+ out of a query::
+
+ subq = session.query(Address).\
+ filter(Address.email_address == 'ed@foo.com').\
+ subquery()
+
+
+ q = session.query(User).join(
+ subq, User.id == subq.c.user_id
+ )
+
+ Joining to a subquery in terms of a specific relationship and/or
+ target entity may be achieved by linking the subquery to the
+ entity using :func:`_orm.aliased`::
+
+ subq = session.query(Address).\
+ filter(Address.email_address == 'ed@foo.com').\
+ subquery()
+
+ address_subq = aliased(Address, subq)
+
+ q = session.query(User).join(
+ User.addresses.of_type(address_subq)
+ )
+
+
+ **Controlling what to Join From**
+
+ In cases where the left side of the current state of
+ :class:`_query.Query` is not in line with what we want to join from,
+ the :meth:`_query.Query.select_from` method may be used::
+
+ q = session.query(Address).select_from(User).\
+ join(User.addresses).\
+ filter(User.name == 'ed')
+
+ Which will produce SQL similar to::
+
+ SELECT address.* FROM user
+ JOIN address ON user.id=address.user_id
+ WHERE user.name = :name_1
+
+ .. seealso::
+
+ :meth:`_sql.Select.join` - v2 equivalent method.
+
+ :param \*props: Incoming arguments for :meth:`_query.Query.join`,
+ the props collection in modern use should be considered to be a one
+ or two argument form, either as a single "target" entity or ORM
+ attribute-bound relationship, or as a target entity plus an "on
+ clause" which may be a SQL expression or ORM attribute-bound
+ relationship.
+
+ :param isouter=False: If True, the join used will be a left outer join,
+ just as if the :meth:`_query.Query.outerjoin` method were called.
+
+ :param full=False: render FULL OUTER JOIN; implies ``isouter``.
+
+ """
+
+ join_target = coercions.expect(
+ roles.JoinTargetRole,
+ target,
+ apply_propagate_attrs=self,
+ legacy=True,
+ )
+ if onclause is not None:
+ onclause_element = coercions.expect(
+ roles.OnClauseRole, onclause, legacy=True
+ )
+ else:
+ onclause_element = None
+
+ self._setup_joins += (
+ (
+ join_target,
+ onclause_element,
+ None,
+ {
+ "isouter": isouter,
+ "full": full,
+ },
+ ),
+ )
+
+ self.__dict__.pop("_last_joined_entity", None)
+ return self
+
+ def outerjoin(
+ self,
+ target: _JoinTargetArgument,
+ onclause: Optional[_OnClauseArgument] = None,
+ *,
+ full: bool = False,
+ ) -> Self:
+ """Create a left outer join against this ``Query`` object's criterion
+ and apply generatively, returning the newly resulting ``Query``.
+
+ Usage is the same as the ``join()`` method.
+
+ .. seealso::
+
+ :meth:`_sql.Select.outerjoin` - v2 equivalent method.
+
+ """
+ return self.join(target, onclause=onclause, isouter=True, full=full)
+
+ @_generative
+ @_assertions(_no_statement_condition)
+ def reset_joinpoint(self) -> Self:
+ """Return a new :class:`.Query`, where the "join point" has
+ been reset back to the base FROM entities of the query.
+
+ This method is usually used in conjunction with the
+ ``aliased=True`` feature of the :meth:`~.Query.join`
+ method. See the example in :meth:`~.Query.join` for how
+ this is used.
+
+ """
+ self._last_joined_entity = None
+
+ return self
+
+ @_generative
+ @_assertions(_no_clauseelement_condition)
+ def select_from(self, *from_obj: _FromClauseArgument) -> Self:
+ r"""Set the FROM clause of this :class:`.Query` explicitly.
+
+ :meth:`.Query.select_from` is often used in conjunction with
+ :meth:`.Query.join` in order to control which entity is selected
+ from on the "left" side of the join.
+
+ The entity or selectable object here effectively replaces the
+ "left edge" of any calls to :meth:`~.Query.join`, when no
+ joinpoint is otherwise established - usually, the default "join
+ point" is the leftmost entity in the :class:`~.Query` object's
+ list of entities to be selected.
+
+ A typical example::
+
+ q = session.query(Address).select_from(User).\
+ join(User.addresses).\
+ filter(User.name == 'ed')
+
+ Which produces SQL equivalent to::
+
+ SELECT address.* FROM user
+ JOIN address ON user.id=address.user_id
+ WHERE user.name = :name_1
+
+ :param \*from_obj: collection of one or more entities to apply
+ to the FROM clause. Entities can be mapped classes,
+ :class:`.AliasedClass` objects, :class:`.Mapper` objects
+ as well as core :class:`.FromClause` elements like subqueries.
+
+ .. seealso::
+
+ :meth:`~.Query.join`
+
+ :meth:`.Query.select_entity_from`
+
+ :meth:`_sql.Select.select_from` - v2 equivalent method.
+
+ """
+
+ self._set_select_from(from_obj, False)
+ return self
+
+ def __getitem__(self, item: Any) -> Any:
+ return orm_util._getitem(
+ self,
+ item,
+ )
+
+ @_generative
+ @_assertions(_no_statement_condition)
+ def slice(
+ self,
+ start: int,
+ stop: int,
+ ) -> Self:
+ """Computes the "slice" of the :class:`_query.Query` represented by
+ the given indices and returns the resulting :class:`_query.Query`.
+
+ The start and stop indices behave like the argument to Python's
+ built-in :func:`range` function. This method provides an
+ alternative to using ``LIMIT``/``OFFSET`` to get a slice of the
+ query.
+
+ For example, ::
+
+ session.query(User).order_by(User.id).slice(1, 3)
+
+ renders as
+
+ .. sourcecode:: sql
+
+ SELECT users.id AS users_id,
+ users.name AS users_name
+ FROM users ORDER BY users.id
+ LIMIT ? OFFSET ?
+ (2, 1)
+
+ .. seealso::
+
+ :meth:`_query.Query.limit`
+
+ :meth:`_query.Query.offset`
+
+ :meth:`_sql.Select.slice` - v2 equivalent method.
+
+ """
+
+ self._limit_clause, self._offset_clause = sql_util._make_slice(
+ self._limit_clause, self._offset_clause, start, stop
+ )
+ return self
+
+ @_generative
+ @_assertions(_no_statement_condition)
+ def limit(self, limit: _LimitOffsetType) -> Self:
+ """Apply a ``LIMIT`` to the query and return the newly resulting
+ ``Query``.
+
+ .. seealso::
+
+ :meth:`_sql.Select.limit` - v2 equivalent method.
+
+ """
+ self._limit_clause = sql_util._offset_or_limit_clause(limit)
+ return self
+
+ @_generative
+ @_assertions(_no_statement_condition)
+ def offset(self, offset: _LimitOffsetType) -> Self:
+ """Apply an ``OFFSET`` to the query and return the newly resulting
+ ``Query``.
+
+ .. seealso::
+
+ :meth:`_sql.Select.offset` - v2 equivalent method.
+ """
+ self._offset_clause = sql_util._offset_or_limit_clause(offset)
+ return self
+
+ @_generative
+ @_assertions(_no_statement_condition)
+ def distinct(self, *expr: _ColumnExpressionArgument[Any]) -> Self:
+ r"""Apply a ``DISTINCT`` to the query and return the newly resulting
+ ``Query``.
+
+
+ .. note::
+
+ The ORM-level :meth:`.distinct` call includes logic that will
+ automatically add columns from the ORDER BY of the query to the
+ columns clause of the SELECT statement, to satisfy the common need
+ of the database backend that ORDER BY columns be part of the SELECT
+ list when DISTINCT is used. These columns *are not* added to the
+ list of columns actually fetched by the :class:`_query.Query`,
+ however,
+ so would not affect results. The columns are passed through when
+ using the :attr:`_query.Query.statement` accessor, however.
+
+ .. deprecated:: 2.0 This logic is deprecated and will be removed
+ in SQLAlchemy 2.0. See :ref:`migration_20_query_distinct`
+ for a description of this use case in 2.0.
+
+ .. seealso::
+
+ :meth:`_sql.Select.distinct` - v2 equivalent method.
+
+ :param \*expr: optional column expressions. When present,
+ the PostgreSQL dialect will render a ``DISTINCT ON (<expressions>)``
+ construct.
+
+ .. deprecated:: 1.4 Using \*expr in other dialects is deprecated
+ and will raise :class:`_exc.CompileError` in a future version.
+
+ """
+ if expr:
+ self._distinct = True
+ self._distinct_on = self._distinct_on + tuple(
+ coercions.expect(roles.ByOfRole, e) for e in expr
+ )
+ else:
+ self._distinct = True
+ return self
+
+ def all(self) -> List[_T]:
+ """Return the results represented by this :class:`_query.Query`
+ as a list.
+
+ This results in an execution of the underlying SQL statement.
+
+ .. warning:: The :class:`_query.Query` object,
+ when asked to return either
+ a sequence or iterator that consists of full ORM-mapped entities,
+ will **deduplicate entries based on primary key**. See the FAQ for
+ more details.
+
+ .. seealso::
+
+ :ref:`faq_query_deduplicating`
+
+ .. seealso::
+
+ :meth:`_engine.Result.all` - v2 comparable method.
+
+ :meth:`_engine.Result.scalars` - v2 comparable method.
+ """
+ return self._iter().all() # type: ignore
+
+ @_generative
+ @_assertions(_no_clauseelement_condition)
+ def from_statement(self, statement: ExecutableReturnsRows) -> Self:
+ """Execute the given SELECT statement and return results.
+
+ This method bypasses all internal statement compilation, and the
+ statement is executed without modification.
+
+ The statement is typically either a :func:`_expression.text`
+ or :func:`_expression.select` construct, and should return the set
+ of columns
+ appropriate to the entity class represented by this
+ :class:`_query.Query`.
+
+ .. seealso::
+
+ :meth:`_sql.Select.from_statement` - v2 comparable method.
+
+ """
+ statement = coercions.expect(
+ roles.SelectStatementRole, statement, apply_propagate_attrs=self
+ )
+ self._statement = statement
+ return self
+
+ def first(self) -> Optional[_T]:
+ """Return the first result of this ``Query`` or
+ None if the result doesn't contain any row.
+
+ first() applies a limit of one within the generated SQL, so that
+ only one primary entity row is generated on the server side
+ (note this may consist of multiple result rows if join-loaded
+ collections are present).
+
+ Calling :meth:`_query.Query.first`
+ results in an execution of the underlying
+ query.
+
+ .. seealso::
+
+ :meth:`_query.Query.one`
+
+ :meth:`_query.Query.one_or_none`
+
+ :meth:`_engine.Result.first` - v2 comparable method.
+
+ :meth:`_engine.Result.scalars` - v2 comparable method.
+
+ """
+ # replicates limit(1) behavior
+ if self._statement is not None:
+ return self._iter().first() # type: ignore
+ else:
+ return self.limit(1)._iter().first() # type: ignore
+
+ def one_or_none(self) -> Optional[_T]:
+ """Return at most one result or raise an exception.
+
+ Returns ``None`` if the query selects
+ no rows. Raises ``sqlalchemy.orm.exc.MultipleResultsFound``
+ if multiple object identities are returned, or if multiple
+ rows are returned for a query that returns only scalar values
+ as opposed to full identity-mapped entities.
+
+ Calling :meth:`_query.Query.one_or_none`
+ results in an execution of the
+ underlying query.
+
+ .. seealso::
+
+ :meth:`_query.Query.first`
+
+ :meth:`_query.Query.one`
+
+ :meth:`_engine.Result.one_or_none` - v2 comparable method.
+
+ :meth:`_engine.Result.scalar_one_or_none` - v2 comparable method.
+
+ """
+ return self._iter().one_or_none() # type: ignore
+
+ def one(self) -> _T:
+ """Return exactly one result or raise an exception.
+
+ Raises ``sqlalchemy.orm.exc.NoResultFound`` if the query selects
+ no rows. Raises ``sqlalchemy.orm.exc.MultipleResultsFound``
+ if multiple object identities are returned, or if multiple
+ rows are returned for a query that returns only scalar values
+ as opposed to full identity-mapped entities.
+
+ Calling :meth:`.one` results in an execution of the underlying query.
+
+ .. seealso::
+
+ :meth:`_query.Query.first`
+
+ :meth:`_query.Query.one_or_none`
+
+ :meth:`_engine.Result.one` - v2 comparable method.
+
+ :meth:`_engine.Result.scalar_one` - v2 comparable method.
+
+ """
+ return self._iter().one() # type: ignore
+
+ def scalar(self) -> Any:
+ """Return the first element of the first result or None
+ if no rows present. If multiple rows are returned,
+ raises MultipleResultsFound.
+
+ >>> session.query(Item).scalar()
+ <Item>
+ >>> session.query(Item.id).scalar()
+ 1
+ >>> session.query(Item.id).filter(Item.id < 0).scalar()
+ None
+ >>> session.query(Item.id, Item.name).scalar()
+ 1
+ >>> session.query(func.count(Parent.id)).scalar()
+ 20
+
+ This results in an execution of the underlying query.
+
+ .. seealso::
+
+ :meth:`_engine.Result.scalar` - v2 comparable method.
+
+ """
+ # TODO: not sure why we can't use result.scalar() here
+ try:
+ ret = self.one()
+ if not isinstance(ret, collections_abc.Sequence):
+ return ret
+ return ret[0]
+ except sa_exc.NoResultFound:
+ return None
+
+ def __iter__(self) -> Iterator[_T]:
+ result = self._iter()
+ try:
+ yield from result # type: ignore
+ except GeneratorExit:
+ # issue #8710 - direct iteration is not re-usable after
+ # an iterable block is broken, so close the result
+ result._soft_close()
+ raise
+
+ def _iter(self) -> Union[ScalarResult[_T], Result[_T]]:
+ # new style execution.
+ params = self._params
+
+ statement = self._statement_20()
+ result: Union[ScalarResult[_T], Result[_T]] = self.session.execute(
+ statement,
+ params,
+ execution_options={"_sa_orm_load_options": self.load_options},
+ )
+
+ # legacy: automatically set scalars, unique
+ if result._attributes.get("is_single_entity", False):
+ result = cast("Result[_T]", result).scalars()
+
+ if (
+ result._attributes.get("filtered", False)
+ and not self.load_options._yield_per
+ ):
+ result = result.unique()
+
+ return result
+
+ def __str__(self) -> str:
+ statement = self._statement_20()
+
+ try:
+ bind = (
+ self._get_bind_args(statement, self.session.get_bind)
+ if self.session
+ else None
+ )
+ except sa_exc.UnboundExecutionError:
+ bind = None
+
+ return str(statement.compile(bind))
+
+ def _get_bind_args(self, statement: Any, fn: Any, **kw: Any) -> Any:
+ return fn(clause=statement, **kw)
+
+ @property
+ def column_descriptions(self) -> List[ORMColumnDescription]:
+ """Return metadata about the columns which would be
+ returned by this :class:`_query.Query`.
+
+ Format is a list of dictionaries::
+
+ user_alias = aliased(User, name='user2')
+ q = sess.query(User, User.id, user_alias)
+
+ # this expression:
+ q.column_descriptions
+
+ # would return:
+ [
+ {
+ 'name':'User',
+ 'type':User,
+ 'aliased':False,
+ 'expr':User,
+ 'entity': User
+ },
+ {
+ 'name':'id',
+ 'type':Integer(),
+ 'aliased':False,
+ 'expr':User.id,
+ 'entity': User
+ },
+ {
+ 'name':'user2',
+ 'type':User,
+ 'aliased':True,
+ 'expr':user_alias,
+ 'entity': user_alias
+ }
+ ]
+
+ .. seealso::
+
+ This API is available using :term:`2.0 style` queries as well,
+ documented at:
+
+ * :ref:`queryguide_inspection`
+
+ * :attr:`.Select.column_descriptions`
+
+ """
+
+ return _column_descriptions(self, legacy=True)
+
+ @util.deprecated(
+ "2.0",
+ "The :meth:`_orm.Query.instances` method is deprecated and will "
+ "be removed in a future release. "
+ "Use the Select.from_statement() method or aliased() construct in "
+ "conjunction with Session.execute() instead.",
+ )
+ def instances(
+ self,
+ result_proxy: CursorResult[Any],
+ context: Optional[QueryContext] = None,
+ ) -> Any:
+ """Return an ORM result given a :class:`_engine.CursorResult` and
+ :class:`.QueryContext`.
+
+ """
+ if context is None:
+ util.warn_deprecated(
+ "Using the Query.instances() method without a context "
+ "is deprecated and will be disallowed in a future release. "
+ "Please make use of :meth:`_query.Query.from_statement` "
+ "for linking ORM results to arbitrary select constructs.",
+ version="1.4",
+ )
+ compile_state = self._compile_state(for_statement=False)
+
+ context = QueryContext(
+ compile_state,
+ compile_state.statement,
+ self._params,
+ self.session,
+ self.load_options,
+ )
+
+ result = loading.instances(result_proxy, context)
+
+ # legacy: automatically set scalars, unique
+ if result._attributes.get("is_single_entity", False):
+ result = result.scalars() # type: ignore
+
+ if result._attributes.get("filtered", False):
+ result = result.unique()
+
+ # TODO: isn't this supposed to be a list?
+ return result
+
+ @util.became_legacy_20(
+ ":meth:`_orm.Query.merge_result`",
+ alternative="The method is superseded by the "
+ ":func:`_orm.merge_frozen_result` function.",
+ enable_warnings=False, # warnings occur via loading.merge_result
+ )
+ def merge_result(
+ self,
+ iterator: Union[
+ FrozenResult[Any], Iterable[Sequence[Any]], Iterable[object]
+ ],
+ load: bool = True,
+ ) -> Union[FrozenResult[Any], Iterable[Any]]:
+ """Merge a result into this :class:`_query.Query` object's Session.
+
+ Given an iterator returned by a :class:`_query.Query`
+ of the same structure
+ as this one, return an identical iterator of results, with all mapped
+ instances merged into the session using :meth:`.Session.merge`. This
+ is an optimized method which will merge all mapped instances,
+ preserving the structure of the result rows and unmapped columns with
+ less method overhead than that of calling :meth:`.Session.merge`
+ explicitly for each value.
+
+ The structure of the results is determined based on the column list of
+ this :class:`_query.Query` - if these do not correspond,
+ unchecked errors
+ will occur.
+
+ The 'load' argument is the same as that of :meth:`.Session.merge`.
+
+ For an example of how :meth:`_query.Query.merge_result` is used, see
+ the source code for the example :ref:`examples_caching`, where
+ :meth:`_query.Query.merge_result` is used to efficiently restore state
+ from a cache back into a target :class:`.Session`.
+
+ """
+
+ return loading.merge_result(self, iterator, load)
+
+ def exists(self) -> Exists:
+ """A convenience method that turns a query into an EXISTS subquery
+ of the form EXISTS (SELECT 1 FROM ... WHERE ...).
+
+ e.g.::
+
+ q = session.query(User).filter(User.name == 'fred')
+ session.query(q.exists())
+
+ Producing SQL similar to::
+
+ SELECT EXISTS (
+ SELECT 1 FROM users WHERE users.name = :name_1
+ ) AS anon_1
+
+ The EXISTS construct is usually used in the WHERE clause::
+
+ session.query(User.id).filter(q.exists()).scalar()
+
+ Note that some databases such as SQL Server don't allow an
+ EXISTS expression to be present in the columns clause of a
+ SELECT. To select a simple boolean value based on the exists
+ as a WHERE, use :func:`.literal`::
+
+ from sqlalchemy import literal
+
+ session.query(literal(True)).filter(q.exists()).scalar()
+
+ .. seealso::
+
+ :meth:`_sql.Select.exists` - v2 comparable method.
+
+ """
+
+ # .add_columns() for the case that we are a query().select_from(X),
+ # so that ".statement" can be produced (#2995) but also without
+ # omitting the FROM clause from a query(X) (#2818);
+ # .with_only_columns() after we have a core select() so that
+ # we get just "SELECT 1" without any entities.
+
+ inner = (
+ self.enable_eagerloads(False)
+ .add_columns(sql.literal_column("1"))
+ .set_label_style(LABEL_STYLE_TABLENAME_PLUS_COL)
+ ._get_select_statement_only()
+ .with_only_columns(1)
+ )
+
+ ezero = self._entity_from_pre_ent_zero()
+ if ezero is not None:
+ inner = inner.select_from(ezero)
+
+ return sql.exists(inner)
+
+ def count(self) -> int:
+ r"""Return a count of rows this the SQL formed by this :class:`Query`
+ would return.
+
+ This generates the SQL for this Query as follows::
+
+ SELECT count(1) AS count_1 FROM (
+ SELECT <rest of query follows...>
+ ) AS anon_1
+
+ The above SQL returns a single row, which is the aggregate value
+ of the count function; the :meth:`_query.Query.count`
+ method then returns
+ that single integer value.
+
+ .. warning::
+
+ It is important to note that the value returned by
+ count() is **not the same as the number of ORM objects that this
+ Query would return from a method such as the .all() method**.
+ The :class:`_query.Query` object,
+ when asked to return full entities,
+ will **deduplicate entries based on primary key**, meaning if the
+ same primary key value would appear in the results more than once,
+ only one object of that primary key would be present. This does
+ not apply to a query that is against individual columns.
+
+ .. seealso::
+
+ :ref:`faq_query_deduplicating`
+
+ For fine grained control over specific columns to count, to skip the
+ usage of a subquery or otherwise control of the FROM clause, or to use
+ other aggregate functions, use :attr:`~sqlalchemy.sql.expression.func`
+ expressions in conjunction with :meth:`~.Session.query`, i.e.::
+
+ from sqlalchemy import func
+
+ # count User records, without
+ # using a subquery.
+ session.query(func.count(User.id))
+
+ # return count of user "id" grouped
+ # by "name"
+ session.query(func.count(User.id)).\
+ group_by(User.name)
+
+ from sqlalchemy import distinct
+
+ # count distinct "name" values
+ session.query(func.count(distinct(User.name)))
+
+ .. seealso::
+
+ :ref:`migration_20_query_usage`
+
+ """
+ col = sql.func.count(sql.literal_column("*"))
+ return ( # type: ignore
+ self._legacy_from_self(col).enable_eagerloads(False).scalar()
+ )
+
+ def delete(
+ self, synchronize_session: SynchronizeSessionArgument = "auto"
+ ) -> int:
+ r"""Perform a DELETE with an arbitrary WHERE clause.
+
+ Deletes rows matched by this query from the database.
+
+ E.g.::
+
+ sess.query(User).filter(User.age == 25).\
+ delete(synchronize_session=False)
+
+ sess.query(User).filter(User.age == 25).\
+ delete(synchronize_session='evaluate')
+
+ .. warning::
+
+ See the section :ref:`orm_expression_update_delete` for important
+ caveats and warnings, including limitations when using bulk UPDATE
+ and DELETE with mapper inheritance configurations.
+
+ :param synchronize_session: chooses the strategy to update the
+ attributes on objects in the session. See the section
+ :ref:`orm_expression_update_delete` for a discussion of these
+ strategies.
+
+ :return: the count of rows matched as returned by the database's
+ "row count" feature.
+
+ .. seealso::
+
+ :ref:`orm_expression_update_delete`
+
+ """
+
+ bulk_del = BulkDelete(self)
+ if self.dispatch.before_compile_delete:
+ for fn in self.dispatch.before_compile_delete:
+ new_query = fn(bulk_del.query, bulk_del)
+ if new_query is not None:
+ bulk_del.query = new_query
+
+ self = bulk_del.query
+
+ delete_ = sql.delete(*self._raw_columns) # type: ignore
+ delete_._where_criteria = self._where_criteria
+ result: CursorResult[Any] = self.session.execute(
+ delete_,
+ self._params,
+ execution_options=self._execution_options.union(
+ {"synchronize_session": synchronize_session}
+ ),
+ )
+ bulk_del.result = result # type: ignore
+ self.session.dispatch.after_bulk_delete(bulk_del)
+ result.close()
+
+ return result.rowcount
+
+ def update(
+ self,
+ values: Dict[_DMLColumnArgument, Any],
+ synchronize_session: SynchronizeSessionArgument = "auto",
+ update_args: Optional[Dict[Any, Any]] = None,
+ ) -> int:
+ r"""Perform an UPDATE with an arbitrary WHERE clause.
+
+ Updates rows matched by this query in the database.
+
+ E.g.::
+
+ sess.query(User).filter(User.age == 25).\
+ update({User.age: User.age - 10}, synchronize_session=False)
+
+ sess.query(User).filter(User.age == 25).\
+ update({"age": User.age - 10}, synchronize_session='evaluate')
+
+ .. warning::
+
+ See the section :ref:`orm_expression_update_delete` for important
+ caveats and warnings, including limitations when using arbitrary
+ UPDATE and DELETE with mapper inheritance configurations.
+
+ :param values: a dictionary with attributes names, or alternatively
+ mapped attributes or SQL expressions, as keys, and literal
+ values or sql expressions as values. If :ref:`parameter-ordered
+ mode <tutorial_parameter_ordered_updates>` is desired, the values can
+ be passed as a list of 2-tuples; this requires that the
+ :paramref:`~sqlalchemy.sql.expression.update.preserve_parameter_order`
+ flag is passed to the :paramref:`.Query.update.update_args` dictionary
+ as well.
+
+ :param synchronize_session: chooses the strategy to update the
+ attributes on objects in the session. See the section
+ :ref:`orm_expression_update_delete` for a discussion of these
+ strategies.
+
+ :param update_args: Optional dictionary, if present will be passed
+ to the underlying :func:`_expression.update`
+ construct as the ``**kw`` for
+ the object. May be used to pass dialect-specific arguments such
+ as ``mysql_limit``, as well as other special arguments such as
+ :paramref:`~sqlalchemy.sql.expression.update.preserve_parameter_order`.
+
+ :return: the count of rows matched as returned by the database's
+ "row count" feature.
+
+
+ .. seealso::
+
+ :ref:`orm_expression_update_delete`
+
+ """
+
+ update_args = update_args or {}
+
+ bulk_ud = BulkUpdate(self, values, update_args)
+
+ if self.dispatch.before_compile_update:
+ for fn in self.dispatch.before_compile_update:
+ new_query = fn(bulk_ud.query, bulk_ud)
+ if new_query is not None:
+ bulk_ud.query = new_query
+ self = bulk_ud.query
+
+ upd = sql.update(*self._raw_columns) # type: ignore
+
+ ppo = update_args.pop("preserve_parameter_order", False)
+ if ppo:
+ upd = upd.ordered_values(*values) # type: ignore
+ else:
+ upd = upd.values(values)
+ if update_args:
+ upd = upd.with_dialect_options(**update_args)
+
+ upd._where_criteria = self._where_criteria
+ result: CursorResult[Any] = self.session.execute(
+ upd,
+ self._params,
+ execution_options=self._execution_options.union(
+ {"synchronize_session": synchronize_session}
+ ),
+ )
+ bulk_ud.result = result # type: ignore
+ self.session.dispatch.after_bulk_update(bulk_ud)
+ result.close()
+ return result.rowcount
+
+ def _compile_state(
+ self, for_statement: bool = False, **kw: Any
+ ) -> ORMCompileState:
+ """Create an out-of-compiler ORMCompileState object.
+
+ The ORMCompileState object is normally created directly as a result
+ of the SQLCompiler.process() method being handed a Select()
+ or FromStatement() object that uses the "orm" plugin. This method
+ provides a means of creating this ORMCompileState object directly
+ without using the compiler.
+
+ This method is used only for deprecated cases, which include
+ the .from_self() method for a Query that has multiple levels
+ of .from_self() in use, as well as the instances() method. It is
+ also used within the test suite to generate ORMCompileState objects
+ for test purposes.
+
+ """
+
+ stmt = self._statement_20(for_statement=for_statement, **kw)
+ assert for_statement == stmt._compile_options._for_statement
+
+ # this chooses between ORMFromStatementCompileState and
+ # ORMSelectCompileState. We could also base this on
+ # query._statement is not None as we have the ORM Query here
+ # however this is the more general path.
+ compile_state_cls = cast(
+ ORMCompileState,
+ ORMCompileState._get_plugin_class_for_plugin(stmt, "orm"),
+ )
+
+ return compile_state_cls.create_for_statement(stmt, None)
+
+ def _compile_context(self, for_statement: bool = False) -> QueryContext:
+ compile_state = self._compile_state(for_statement=for_statement)
+ context = QueryContext(
+ compile_state,
+ compile_state.statement,
+ self._params,
+ self.session,
+ self.load_options,
+ )
+
+ return context
+
+
+class AliasOption(interfaces.LoaderOption):
+ inherit_cache = False
+
+ @util.deprecated(
+ "1.4",
+ "The :class:`.AliasOption` object is not necessary "
+ "for entities to be matched up to a query that is established "
+ "via :meth:`.Query.from_statement` and now does nothing.",
+ )
+ def __init__(self, alias: Union[Alias, Subquery]):
+ r"""Return a :class:`.MapperOption` that will indicate to the
+ :class:`_query.Query`
+ that the main table has been aliased.
+
+ """
+
+ def process_compile_state(self, compile_state: ORMCompileState) -> None:
+ pass
+
+
+class BulkUD:
+ """State used for the orm.Query version of update() / delete().
+
+ This object is now specific to Query only.
+
+ """
+
+ def __init__(self, query: Query[Any]):
+ self.query = query.enable_eagerloads(False)
+ self._validate_query_state()
+ self.mapper = self.query._entity_from_pre_ent_zero()
+
+ def _validate_query_state(self) -> None:
+ for attr, methname, notset, op in (
+ ("_limit_clause", "limit()", None, operator.is_),
+ ("_offset_clause", "offset()", None, operator.is_),
+ ("_order_by_clauses", "order_by()", (), operator.eq),
+ ("_group_by_clauses", "group_by()", (), operator.eq),
+ ("_distinct", "distinct()", False, operator.is_),
+ (
+ "_from_obj",
+ "join(), outerjoin(), select_from(), or from_self()",
+ (),
+ operator.eq,
+ ),
+ (
+ "_setup_joins",
+ "join(), outerjoin(), select_from(), or from_self()",
+ (),
+ operator.eq,
+ ),
+ ):
+ if not op(getattr(self.query, attr), notset):
+ raise sa_exc.InvalidRequestError(
+ "Can't call Query.update() or Query.delete() "
+ "when %s has been called" % (methname,)
+ )
+
+ @property
+ def session(self) -> Session:
+ return self.query.session
+
+
+class BulkUpdate(BulkUD):
+ """BulkUD which handles UPDATEs."""
+
+ def __init__(
+ self,
+ query: Query[Any],
+ values: Dict[_DMLColumnArgument, Any],
+ update_kwargs: Optional[Dict[Any, Any]],
+ ):
+ super().__init__(query)
+ self.values = values
+ self.update_kwargs = update_kwargs
+
+
+class BulkDelete(BulkUD):
+ """BulkUD which handles DELETEs."""
+
+
+class RowReturningQuery(Query[Row[_TP]]):
+ if TYPE_CHECKING:
+
+ def tuples(self) -> Query[_TP]: # type: ignore
+ ...