class BooleanClauseList(ClauseList, ColumnElement):
Undocumented
Class Method | and_ |
Produce a conjunction of expressions joined by AND. |
Class Method | or_ |
Produce a conjunction of expressions joined by OR. |
Class Method | _construct |
Undocumented |
Class Method | _construct_for_whereclause |
Undocumented |
Class Method | _construct_raw |
Undocumented |
Class Method | _process_clauses_for_boolean |
Undocumented |
Method | __init__ |
Undocumented |
Method | _negate |
Undocumented |
Method | self_group |
Apply a 'grouping' to this _expression.ClauseElement . |
Class Variable | __visit_name__ |
Undocumented |
Class Variable | inherit_cache |
Indicate if this .HasCacheKey instance should make use of the cache key generation scheme used by its immediate superclass. |
Instance Variable | _is_implicitly_boolean |
Undocumented |
Instance Variable | clauses |
Undocumented |
Instance Variable | group |
Undocumented |
Instance Variable | group_contents |
Undocumented |
Instance Variable | operator |
Undocumented |
Instance Variable | type |
Undocumented |
Property | _select_iterable |
Undocumented |
Inherited from ClauseList
:
Method | __iter__ |
Undocumented |
Method | __len__ |
Undocumented |
Method | append |
Undocumented |
Class Variable | _is_clause_list |
Undocumented |
Class Variable | _traverse_internals |
Undocumented |
Instance Variable | _text_converter_role |
Undocumented |
Property | _from_objects |
Undocumented |
Inherited from InElementRole
(via ClauseList
):
Class Variable | _role_name |
Undocumented |
Inherited from SQLRole
(via ClauseList
, InElementRole
):
Class Variable | allows_lambda |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from OrderByRole
(via ClauseList
):
Class Variable | _role_name |
Undocumented |
Inherited from AllowsLambdaRole
(via ClauseList
, OrderByRole
):
Class Variable | allows_lambda |
Undocumented |
Inherited from SQLRole
(via ClauseList
, OrderByRole
, ByOfRole
, ColumnListRole
):
Class Variable | allows_lambda |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from ColumnsClauseRole
(via ClauseList
):
Class Variable | _role_name |
Undocumented |
Inherited from AllowsLambdaRole
(via ClauseList
, ColumnsClauseRole
):
Class Variable | allows_lambda |
Undocumented |
Inherited from UsesInspection
(via ClauseList
, ColumnsClauseRole
):
Class Variable | _post_inspect |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from SQLRole
(via ClauseList
, ColumnsClauseRole
, ColumnListRole
):
Class Variable | allows_lambda |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from DMLColumnRole
(via ClauseList
):
Class Variable | _role_name |
Undocumented |
Inherited from SQLRole
(via ClauseList
, DMLColumnRole
):
Class Variable | allows_lambda |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from ClauseElement
(via ClauseList
):
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 | unique_params |
Return a copy with _expression.bindparam elements replaced. |
Method | __bool__ |
Undocumented |
Method | __getstate__ |
Undocumented |
Method | __invert__ |
Undocumented |
Method | __repr__ |
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 | _execute_on_connection |
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_clone_of |
Undocumented |
Class Variable | _is_from_clause |
Undocumented |
Class Variable | _is_from_container |
Undocumented |
Class Variable | _is_immutable |
Undocumented |
Class Variable | _is_lambda_element |
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 ClauseList
, ClauseElement
):
Class Variable | allows_lambda |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from SupportsWrappingAnnotations
(via ClauseList
, 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 ClauseList
, ClauseElement
, SupportsWrappingAnnotations
):
Property | _annotations_cache_key |
Undocumented |
Inherited from MemoizedHasCacheKey
(via ClauseList
, ClauseElement
):
Method | _generate_cache_key |
return a cache key. |
Inherited from HasCacheKey
(via ClauseList
, ClauseElement
, MemoizedHasCacheKey
):
Class Method | _generate_cache_attrs |
generate cache key dispatcher for a new class. |
Class Method | _generate_cache_key_for_object |
Undocumented |
Method | _gen_cache_key |
return an optional cache key. |
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 HasCopyInternals
(via ClauseList
, ClauseElement
):
Method | _copy_internals |
Reassign internal elements to be clones of themselves. |
Inherited from Traversible
(via ClauseList
, ClauseElement
):
Method | get_children |
Return immediate child .visitors.Traversible elements of this .visitors.Traversible . |
Method | __class_getitem__ |
Undocumented |
Inherited from ColumnElement
:
Method | cast |
Produce a type cast, i.e. CAST(<expression> AS <type>). |
Method | label |
Produce a column label, i.e. <columnname> AS <name>. |
Method | operate |
Operate on an argument. |
Method | reverse_operate |
Reverse operate on an argument. |
Method | shares_lineage |
Return True if the given _expression.ColumnElement has a common ancestor to this _expression.ColumnElement . |
Class Variable | foreign_keys |
Undocumented |
Class Variable | key |
The 'key' that in some circumstances refers to this object in a Python namespace. |
Class Variable | primary_key |
Undocumented |
Method | __getattr__ |
Undocumented |
Method | _anon_label |
Undocumented |
Method | _bind_param |
Undocumented |
Method | _compare_name_for_result |
Return True if the given column element compares to this one when targeting within a result row. |
Method | _dedupe_anon_label_idx |
label to apply to a column that is anon labeled, but repeated in the SELECT, so that we have to make an "extra anon" label that disambiguates it from the previous appearance. |
Method | _dedupe_anon_tq_label_idx |
Undocumented |
Method | _expression_label |
a suggested label to use in the case that the column has no name, which should be used if possible as the explicit 'AS <label>' where this expression would normally have an anon label. |
Method | _make_proxy |
Create a new _expression.ColumnElement representing this _expression.ColumnElement as it appears in the select list of a descending selectable. |
Method | _proxy_key |
Undocumented |
Method | _tq_key_label |
A label-based version of 'key' that in some circumstances refers to this object in a Python namespace. |
Method | _uncached_proxy_set |
An 'uncached' version of proxy set. |
Method | comparator |
Undocumented |
Class Variable | _allow_label_resolve |
A flag that can be flipped to prevent a column from being resolvable by string label name. |
Class Variable | _alt_names |
Undocumented |
Class Variable | _proxies |
Undocumented |
Class Variable | _render_label_in_columns_clause |
No summary |
Class Variable | _tq_label |
The named label that can be used to target this column in a result set in a "table qualified" context. |
Property | _anon_key_label |
Provides a constant 'anonymous key label' for this ColumnElement. |
Property | _anon_name_label |
Provides a constant 'anonymous label' for this ColumnElement. |
Property | _anon_tq_key_label |
Undocumented |
Property | _anon_tq_label |
Undocumented |
Property | _key_label |
legacy; renamed to _tq_key_label |
Property | _label |
legacy; renamed to _tq_label |
Property | _non_anon_label |
the 'name' that naturally applies this element when rendered in SQL. |
Property | anon_key_label |
Undocumented |
Property | anon_label |
Undocumented |
Property | base_columns |
Undocumented |
Property | expression |
Return a column expression. |
Property | proxy_set |
Undocumented |
Inherited from ColumnArgumentOrKeyRole
(via ColumnElement
):
Class Variable | _role_name |
Undocumented |
Inherited from SQLRole
(via ColumnElement
, ColumnArgumentOrKeyRole
, ColumnArgumentRole
):
Class Variable | allows_lambda |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from StatementOptionRole
(via ColumnElement
):
Class Variable | _role_name |
Undocumented |
Inherited from SQLRole
(via ColumnElement
, StatementOptionRole
, StructuralRole
):
Class Variable | allows_lambda |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from WhereHavingRole
(via ColumnElement
):
Class Variable | _role_name |
Undocumented |
Inherited from AllowsLambdaRole
(via ColumnElement
, WhereHavingRole
, OnClauseRole
):
Class Variable | allows_lambda |
Undocumented |
Inherited from SQLRole
(via ColumnElement
, WhereHavingRole
, OnClauseRole
, StructuralRole
):
Class Variable | allows_lambda |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from BinaryElementRole
(via ColumnElement
):
Class Variable | _role_name |
Undocumented |
Inherited from SQLRole
(via ColumnElement
, BinaryElementRole
, ExpressionElementRole
):
Class Variable | allows_lambda |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from OrderByRole
(via ColumnElement
):
Class Variable | _role_name |
Undocumented |
Inherited from AllowsLambdaRole
(via ColumnElement
, OrderByRole
):
Class Variable | allows_lambda |
Undocumented |
Inherited from SQLRole
(via ColumnElement
, OrderByRole
, ByOfRole
, ColumnListRole
):
Class Variable | allows_lambda |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from ColumnsClauseRole
(via ColumnElement
):
Class Variable | _role_name |
Undocumented |
Inherited from AllowsLambdaRole
(via ColumnElement
, ColumnsClauseRole
):
Class Variable | allows_lambda |
Undocumented |
Inherited from UsesInspection
(via ColumnElement
, ColumnsClauseRole
):
Class Variable | _post_inspect |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from SQLRole
(via ColumnElement
, ColumnsClauseRole
, ColumnListRole
):
Class Variable | allows_lambda |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from LimitOffsetRole
(via ColumnElement
):
Class Variable | _role_name |
Undocumented |
Inherited from SQLRole
(via ColumnElement
, LimitOffsetRole
):
Class Variable | allows_lambda |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from DMLColumnRole
(via ColumnElement
):
Class Variable | _role_name |
Undocumented |
Inherited from SQLRole
(via ColumnElement
, DMLColumnRole
):
Class Variable | allows_lambda |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from DDLConstraintColumnRole
(via ColumnElement
):
Class Variable | _role_name |
Undocumented |
Inherited from SQLRole
(via ColumnElement
, DDLConstraintColumnRole
):
Class Variable | allows_lambda |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from DDLExpressionRole
(via ColumnElement
):
Class Variable | _role_name |
Undocumented |
Inherited from SQLRole
(via ColumnElement
, DDLExpressionRole
, StructuralRole
):
Class Variable | allows_lambda |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from ColumnOperators
(via ColumnElement
):
Method | __add__ |
Implement the + operator. |
Method | __contains__ |
Undocumented |
Method | __div__ |
Implement the / operator. |
Method | __eq__ |
Implement the == operator. |
Method | __ge__ |
Implement the >= operator. |
Method | __getitem__ |
Implement the [] operator. |
Method | __gt__ |
Implement the > operator. |
Method | __le__ |
Implement the <= operator. |
Method | __lshift__ |
implement the << operator. |
Method | __lt__ |
Implement the < operator. |
Method | __mod__ |
Implement the % operator. |
Method | __mul__ |
Implement the * operator. |
Method | __ne__ |
Implement the != operator. |
Method | __neg__ |
Implement the - operator. |
Method | __radd__ |
Implement the + operator in reverse. |
Method | __rdiv__ |
Implement the / operator in reverse. |
Method | __rmod__ |
Implement the % operator in reverse. |
Method | __rmul__ |
Implement the * operator in reverse. |
Method | __rshift__ |
implement the >> operator. |
Method | __rsub__ |
Implement the - operator in reverse. |
Method | __rtruediv__ |
Implement the // operator in reverse. |
Method | __sub__ |
Implement the - operator. |
Method | __truediv__ |
Implement the // operator. |
Method | all_ |
Produce an _expression.all_ clause against the parent object. |
Method | any_ |
Produce an _expression.any_ clause against the parent object. |
Method | asc |
Produce a _expression.asc clause against the parent object. |
Method | between |
Produce a _expression.between clause against the parent object, given the lower and upper range. |
Method | collate |
Produce a _expression.collate clause against the parent object, given the collation string. |
Method | concat |
Implement the 'concat' operator. |
Method | contains |
Implement the 'contains' operator. |
Method | desc |
Produce a _expression.desc clause against the parent object. |
Method | distinct |
Produce a _expression.distinct clause against the parent object. |
Method | endswith |
Implement the 'endswith' operator. |
Method | ilike |
Implement the ilike operator, e.g. case insensitive LIKE. |
Method | in_ |
Implement the in operator. |
Method | is_ |
Implement the IS operator. |
Method | is_distinct_from |
Implement the IS DISTINCT FROM operator. |
Method | is_not |
Implement the IS NOT operator. |
Method | is_not_distinct_from |
Implement the IS NOT DISTINCT FROM operator. |
Method | like |
Implement the like operator. |
Method | match |
Implements a database-specific 'match' operator. |
Method | not_ilike |
implement the NOT ILIKE operator. |
Method | not_in |
implement the NOT IN operator. |
Method | not_like |
implement the NOT LIKE operator. |
Method | nulls_first |
Produce a _expression.nulls_first clause against the parent object. |
Method | nulls_last |
Produce a _expression.nulls_last clause against the parent object. |
Method | regexp_match |
Implements a database-specific 'regexp match' operator. |
Method | regexp_replace |
Implements a database-specific 'regexp replace' operator. |
Method | startswith |
Implement the startswith operator. |
Class Variable | __slots__ |
Undocumented |
Class Variable | timetuple |
Hack, allows datetime objects to be compared on the LHS. |
Inherited from Operators
(via ColumnElement
, ColumnOperators
):
Method | __and__ |
Implement the & operator. |
Method | __invert__ |
Implement the ~ operator. |
Method | __or__ |
Implement the | operator. |
Method | bool_op |
Return a custom boolean operator. |
Method | op |
Produce a generic operator function. |
Inherited from ClauseElement
(via ColumnElement
):
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 | unique_params |
Return a copy with _expression.bindparam elements replaced. |
Method | __bool__ |
Undocumented |
Method | __getstate__ |
Undocumented |
Method | __invert__ |
Undocumented |
Method | __repr__ |
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 | _execute_on_connection |
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 | _from_objects |
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_lambda_element |
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 ColumnElement
, ClauseElement
):
Class Variable | allows_lambda |
Undocumented |
Class Variable | uses_inspection |
Undocumented |
Inherited from SupportsWrappingAnnotations
(via ColumnElement
, 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 ColumnElement
, ClauseElement
, SupportsWrappingAnnotations
):
Property | _annotations_cache_key |
Undocumented |
Inherited from MemoizedHasCacheKey
(via ColumnElement
, ClauseElement
):
Method | _generate_cache_key |
return a cache key. |
Inherited from HasCacheKey
(via ColumnElement
, ClauseElement
, MemoizedHasCacheKey
):
Class Method | _generate_cache_attrs |
generate cache key dispatcher for a new class. |
Class Method | _generate_cache_key_for_object |
Undocumented |
Method | _gen_cache_key |
return an optional cache key. |
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 HasCopyInternals
(via ColumnElement
, ClauseElement
):
Method | _copy_internals |
Reassign internal elements to be clones of themselves. |
Inherited from Traversible
(via ColumnElement
, ClauseElement
):
Method | get_children |
Return immediate child .visitors.Traversible elements of this .visitors.Traversible . |
Method | __class_getitem__ |
Undocumented |
Produce a conjunction of expressions joined by AND.
E.g.:
from sqlalchemy import and_ stmt = select(users_table).where( and_( users_table.c.name == 'wendy', users_table.c.enrolled == True ) )
The .and_
conjunction is also available using the
Python & operator (though note that compound expressions
need to be parenthesized in order to function with Python
operator precedence behavior):
stmt = select(users_table).where( (users_table.c.name == 'wendy') & (users_table.c.enrolled == True) )
The .and_
operation is also implicit in some cases;
the _expression.Select.where
method for example can be invoked multiple
times against a statement, which will have the effect of each
clause being combined using .and_
:
stmt = select(users_table).\ where(users_table.c.name == 'wendy').\ where(users_table.c.enrolled == True)
The .and_
construct must be given at least one positional
argument in order to be valid; a .and_
construct with no
arguments is ambiguous. To produce an "empty" or dynamically
generated .and_
expression, from a given list of expressions,
a "default" element of True should be specified:
criteria = and_(True, *expressions)
The above expression will compile to SQL as the expression true or 1 = 1, depending on backend, if no other expressions are present. If expressions are present, then the True value is ignored as it does not affect the outcome of an AND expression that has other elements.
.and_
element now requires that at
least one argument is passed; creating the .and_
construct
with no arguments is deprecated, and will emit a deprecation warning
while continuing to produce a blank SQL string.See Also
.or_
Produce a conjunction of expressions joined by OR.
E.g.:
from sqlalchemy import or_ stmt = select(users_table).where( or_( users_table.c.name == 'wendy', users_table.c.name == 'jack' ) )
The .or_
conjunction is also available using the
Python | operator (though note that compound expressions
need to be parenthesized in order to function with Python
operator precedence behavior):
stmt = select(users_table).where( (users_table.c.name == 'wendy') | (users_table.c.name == 'jack') )
The .or_
construct must be given at least one positional
argument in order to be valid; a .or_
construct with no
arguments is ambiguous. To produce an "empty" or dynamically
generated .or_
expression, from a given list of expressions,
a "default" element of False should be specified:
or_criteria = or_(False, *expressions)
The above expression will compile to SQL as the expression false or 0 = 1, depending on backend, if no other expressions are present. If expressions are present, then the False value is ignored as it does not affect the outcome of an OR expression which has other elements.
.or_
element now requires that at
least one argument is passed; creating the .or_
construct
with no arguments is deprecated, and will emit a deprecation warning
while continuing to produce a blank SQL string.See Also
.and_
Undocumented
Apply a 'grouping' to this _expression.ClauseElement
.
This method is overridden by subclasses to return a "grouping"
construct, i.e. parenthesis. In particular it's used by "binary"
expressions to provide a grouping around themselves when placed into a
larger expression, as well as by _expression.select
constructs when placed into the FROM clause of another
_expression.select
. (Note that subqueries should be
normally created using the _expression.Select.alias
method,
as many
platforms require nested SELECT statements to be named).
As expressions are composed together, the application of
self_group
is automatic - end-user code should never
need to use this method directly. Note that SQLAlchemy's
clause constructs take operator precedence into account -
so parenthesis might not be needed, for example, in
an expression like x OR (y AND z) - AND takes precedence
over OR.
The base self_group
method of
_expression.ClauseElement
just returns self.
bool
=
Indicate if this .HasCacheKey
instance should make use of the
cache key generation scheme used by its immediate superclass.
The attribute defaults to None, which indicates that a construct has not yet taken into account whether or not its appropriate for it to participate in caching; this is functionally equivalent to setting the value to False, except that a warning is also emitted.
This flag can be set to True on a particular class, if the SQL that corresponds to the object does not change based on attributes which are local to this class, and not its superclass.
See Also
:ref:`compilerext_caching` - General guideslines for setting the
.HasCacheKey.inherit_cache
attribute for third-party or user
defined SQL constructs.