sqlalchemy.sql.expression.StatementLambdaElement

class documentation

class StatementLambdaElement(roles.AllowsLambdaRole, LambdaElement):

Known subclasses: sqlalchemy.sql.lambdas.LinkedLambdaElement

Represent a composable SQL statement as a _sql.LambdaElement.

The _sql.StatementLambdaElement is constructed using the _sql.lambda_stmt function:

from sqlalchemy import lambda_stmt

stmt = lambda_stmt(lambda: select(table))

Once constructed, additional criteria can be built onto the statement by adding subsequent lambdas, which accept the existing statement object as a single parameter:

stmt += lambda s: s.where(table.c.col == parameter)

New in version 1.4.

See Also

:ref:`engine_lambda_caching`

Method	`add_criteria`	Add new criteria to this `_sql.StatementLambdaElement`.
Method	`spoil`	Return a new `.StatementLambdaElement` that will run all lambdas unconditionally each time.
Method	`__add__`	Undocumented
Method	`_execute_on_connection`	Undocumented
Property	`_effective_plugin_target`	Undocumented
Property	`_execution_options`	Undocumented
Property	`_with_options`	Undocumented

Inherited from AllowsLambdaRole:

Class Variable allows_lambda Undocumented

Inherited from LambdaElement:

Method	`__getattr__`	Undocumented
Method	`__init__`	Undocumented
Method	`__repr__`	Undocumented
Method	`_copy_internals`	Reassign internal elements to be clones of themselves.
Method	`_gen_cache_key`	return an optional cache key.
Method	`_invoke_user_fn`	Undocumented
Method	`_param_dict`	Undocumented
Method	`_retrieve_tracker_rec`	Undocumented
Method	`_setup_binds_for_tracked_expr`	Undocumented
Class Variable	`__visit_name__`	Undocumented
Class Variable	`_is_lambda_element`	Undocumented
Class Variable	`_transforms`	Undocumented
Class Variable	`_traverse_internals`	Undocumented
Class Variable	`parent_lambda`	Undocumented
Instance Variable	`_rec`	Undocumented
Instance Variable	`_resolved_bindparams`	Undocumented
Instance Variable	`closure_cache_key`	Undocumented
Instance Variable	`fn`	Undocumented
Instance Variable	`opts`	Undocumented
Instance Variable	`role`	Undocumented
Instance Variable	`tracker_key`	Undocumented
Property	`_from_objects`	Undocumented
Property	`_is_sequence`	Undocumented
Property	`_resolved`	Undocumented
Property	`_select_iterable`	Undocumented

Inherited from ClauseElement (via LambdaElement):

Method	`compare`	Compare this `_expression.ClauseElement` to the given `_expression.ClauseElement`.
Method	`compile`	Compile this SQL expression.
Method	`params`	Return a copy with `_expression.bindparam` elements replaced.
Method	`self_group`	Apply a 'grouping' to this `_expression.ClauseElement`.
Method	`unique_params`	Return a copy with `_expression.bindparam` elements replaced.
Method	`__bool__`	Undocumented
Method	`__getstate__`	Undocumented
Method	`__invert__`	Undocumented
Method	`__str__`	Undocumented
Method	`_clone`	Create a shallow copy of this ClauseElement.
Method	`_cloned_set`	Return the set consisting all cloned ancestors of this ClauseElement.
Method	`_compile_w_cache`	Undocumented
Method	`_compiler`	Return a compiler appropriate for this ClauseElement, given a Dialect.
Method	`_negate`	Undocumented
Method	`_negate_in_binary`	a hook to allow the right side of a binary expression to respond to a negation of the binary expression.
Method	`_replace_params`	Undocumented
Method	`_set_propagate_attrs`	Undocumented
Method	`_ungroup`	Return this `_expression.ClauseElement` without any groupings.
Method	`_with_binary_element_type`	in the context of binary expression, convert the type of this object to the one given.
Class Variable	`_cache_key_traversal`	Undocumented
Class Variable	`_is_bind_parameter`	Undocumented
Class Variable	`_is_clause_list`	Undocumented
Class Variable	`_is_clone_of`	Undocumented
Class Variable	`_is_from_clause`	Undocumented
Class Variable	`_is_from_container`	Undocumented
Class Variable	`_is_immutable`	Undocumented
Class Variable	`_is_returns_rows`	Undocumented
Class Variable	`_is_select_container`	Undocumented
Class Variable	`_is_select_statement`	Undocumented
Class Variable	`_is_singleton_constant`	Undocumented
Class Variable	`_is_text_clause`	Undocumented
Class Variable	`_is_textual`	Undocumented
Class Variable	`_order_by_label_element`	Undocumented
Class Variable	`bind`	Undocumented
Class Variable	`description`	Undocumented
Class Variable	`is_clause_element`	Undocumented
Class Variable	`is_selectable`	Undocumented
Class Variable	`stringify_dialect`	Undocumented
Class Variable	`supports_execution`	Undocumented
Instance Variable	`_propagate_attrs`	like annotations, however these propagate outwards liberally as SQL constructs are built, and are set up at construction time.
Property	`_constructor`	return the 'constructor' for this ClauseElement.
Property	`entity_namespace`	Undocumented

Inherited from SQLRole (via LambdaElement, ClauseElement):

Class Variable	`allows_lambda`	Undocumented
Class Variable	`uses_inspection`	Undocumented

Inherited from SupportsWrappingAnnotations (via LambdaElement, ClauseElement):

Method	`_annotate`	return a copy of this ClauseElement with annotations updated by the given dictionary.
Method	`_deannotate`	return a copy of this `_expression.ClauseElement` with annotations removed.
Method	`_with_annotations`	return a copy of this ClauseElement with annotations replaced by the given dictionary.

Inherited from SupportsAnnotations (via LambdaElement, ClauseElement, SupportsWrappingAnnotations):

Property _annotations_cache_key Undocumented

Inherited from MemoizedHasCacheKey (via LambdaElement, ClauseElement):

Method _generate_cache_key return a cache key.

Inherited from HasCacheKey (via LambdaElement, ClauseElement, MemoizedHasCacheKey):

Class Variable	`inherit_cache`	Indicate if this `.HasCacheKey` instance should make use of the cache key generation scheme used by its immediate superclass.
Class Method	`_generate_cache_attrs`	generate cache key dispatcher for a new class.
Class Method	`_generate_cache_key_for_object`	Undocumented
Class Variable	`__slots__`	Undocumented
Class Variable	`_hierarchy_supports_caching`	private attribute which may be set to False to prevent the inherit_cache warning from being emitted for a hierarchy of subclasses.
Class Variable	`_is_has_cache_key`	Undocumented

Inherited from Traversible (via LambdaElement, ClauseElement):

Method	`get_children`	Return immediate child `.visitors.Traversible` elements of this `.visitors.Traversible`.
Method	`__class_getitem__`	Undocumented

def add_criteria(self, other, enable_tracking=True, track_on=None, track_closure_variables=True, track_bound_values=True):

Add new criteria to this _sql.StatementLambdaElement.

E.g.:

>>> def my_stmt(parameter):
...     stmt = lambda_stmt(
...         lambda: select(table.c.x, table.c.y),
...     )
...     stmt = stmt.add_criteria(
...         lambda: table.c.x > parameter
...     )
...     return stmt

The _sql.StatementLambdaElement.add_criteria method is equivalent to using the Python addition operator to add a new lambda, except that additional arguments may be added including track_closure_values and track_on:

>>> def my_stmt(self, foo):
...     stmt = lambda_stmt(
...         lambda: select(func.max(foo.x, foo.y)),
...         track_closure_variables=False
...     )
...     stmt = stmt.add_criteria(
...         lambda: self.where_criteria,
...         track_on=[self]
...     )
...     return stmt

See _sql.lambda_stmt for a description of the parameters accepted.

def spoil(self):

Return a new .StatementLambdaElement that will run all lambdas unconditionally each time.

def __add__(self, other):

Undocumented

def _execute_on_connection(self, connection, multiparams, params, execution_options):

overrides sqlalchemy.sql.expression.ClauseElement._execute_on_connection

Undocumented

@property
_effective_plugin_target =

Undocumented

@property
_execution_options =

Undocumented

@property
_with_options =

Undocumented