Insert, Updates, Deletes ¶

from sqlalchemy import delete
stmt = (
    delete(user_table).
    where(user_table.c.id == 5)
Similar functionality is available via the
TableClause.delete() method on
Table.
Parameters:
table¶ – The table to delete rows from.
See also
Using UPDATE and DELETE Statements - in the SQLAlchemy Unified Tutorial
function sqlalchemy.sql.expression.insert(table: _DMLTableArgument) → Insert¶
Construct an Insert object.
E.g.:
from sqlalchemy import insert
stmt = (
    insert(user_table).
    values(name='username', fullname='Full Username')
Similar functionality is available via the
TableClause.insert() method on
Table.
See also
Using INSERT Statements - in the SQLAlchemy Unified Tutorial
Parameters:
table¶ – TableClause
which is the subject of the
insert.
values¶ – collection of values to be inserted; see
Insert.values()
for a description of allowed formats here.
Can be omitted entirely; a Insert construct
will also dynamically render the VALUES clause at execution time
based on the parameters passed to Connection.execute().
inline¶ – if True, no attempt will be made to retrieve the
SQL-generated default values to be provided within the statement;
in particular,
this allows SQL expressions to be rendered ‘inline’ within the
statement without the need to pre-execute them beforehand; for
backends that support “returning”, this turns off the “implicit
returning” feature for the statement.
If both insert.values and compile-time bind
parameters are present, the compile-time bind parameters override the
information specified within insert.values on a
per-key basis.




    

The keys within Insert.values can be either
Column objects or their string
identifiers. Each key may reference one of:
a literal data value (i.e. string, number, etc.);
a Column object;
a SELECT statement.
If a SELECT statement is specified which references this
INSERT statement’s table, the statement will be correlated
against the INSERT statement.
See also
Using INSERT Statements - in the SQLAlchemy Unified Tutorial
function sqlalchemy.sql.expression.update(table: _DMLTableArgument) → Update¶
Construct an Update object.
E.g.:
from sqlalchemy import update
stmt = (
    update(user_table).
    where(user_table.c.id == 5).
    values(name='user #5')
Similar functionality is available via the
TableClause.update() method on
Table.
Parameters:
table¶ – A Table
object representing the database
table to be updated.
See also
Using UPDATE and DELETE Statements - in the SQLAlchemy Unified Tutorial
DML Class Documentation Constructors¶
Class documentation for the constructors listed at
DML Foundational Constructors.
Object Name
Description
Delete
Represent a DELETE construct.
Insert
Represent an INSERT construct.
Update
Represent an Update construct.
UpdateBase
Form the base for INSERT, UPDATE, and DELETE statements.
ValuesBase
Supplies support for ValuesBase.values() to
INSERT and UPDATE constructs.
class sqlalchemy.sql.expression.Delete¶
Represent a DELETE construct.
The Delete object is created using the
delete() function.
Members
where(), returning()
Class signature
class sqlalchemy.sql.expression.Delete (sqlalchemy.sql.expression.DMLWhereBase, sqlalchemy.sql.expression.UpdateBase)
method sqlalchemy.sql.expression.Delete.where(*whereclause: _ColumnExpressionArgument[bool]) → Self¶
inherited from the DMLWhereBase.where() method of DMLWhereBase
Return a new construct with the given expression(s) added to
its WHERE clause, joined to the existing clause via AND, if any.
Both Update.where() and Delete.where()
support multiple-table forms, including database-specific
UPDATE...FROM as well as DELETE..USING.  For backends that
don’t have multiple-table support, a backend agnostic approach
to using multiple tables is to make use of correlated subqueries.
See the linked tutorial sections below for examples.
See also
Correlated Updates
UPDATE..FROM
Multiple Table Deletes
method sqlalchemy.sql.expression.Delete.returning(*cols: _ColumnsClauseArgument[Any], sort_by_parameter_order: bool = False, **_UpdateBase__kw: Any) → UpdateBase¶
inherited from the UpdateBase.returning() method of UpdateBase
Add a RETURNING or equivalent clause to this statement.
e.g.:
>>> stmt = (
...     table.update()
...     .where(table.c.data == "value")
...     .values(status="X")
...     .returning(table.c.server_flag, table.c.updated_timestamp)
... )
>>> print(stmt)
UPDATE some_table SET status=:status
WHERE some_table.data = :data_1
RETURNING some_table.server_flag, some_table.updated_timestamp
The method may be invoked multiple times to add new entries to the
list of expressions to be returned.
New in version 1.4.0b2: The method may be invoked multiple times to
add new entries to the list of expressions to be returned.
The given collection of column expressions should be derived from the
table that is the target of the INSERT, UPDATE, or DELETE.  While
Column objects are typical, the elements can also be
expressions:
>>> stmt = table.insert().returning(
...     (table.c.first_name + " " + table.c.last_name).label("fullname")
... )
>>> print(stmt)
INSERT INTO some_table (first_name, last_name)
VALUES (:first_name, :last_name)
RETURNING some_table.first_name || :first_name_1 || some_table.last_name AS fullname
Upon compilation, a RETURNING clause, or database equivalent,
will be rendered within the statement.   For INSERT and UPDATE,
the values are the newly inserted/updated values.  For DELETE,
the values are those of the rows which were deleted.
Upon execution, the values of the columns to be returned are made
available via the result set and can be iterated using
CursorResult.fetchone() and similar.
For DBAPIs which do not
natively support returning values (i.e. cx_oracle), SQLAlchemy will
approximate this behavior at the result level so that a reasonable
amount of behavioral neutrality is provided.
Note that not all databases/DBAPIs
support RETURNING.   For those backends with no support,
an exception is raised upon compilation and/or execution.
For those who do support it, the functionality across backends
varies greatly, including restrictions on executemany()
and other statements which return multiple rows. Please
read the documentation notes for the database in use in
order to determine the availability of RETURNING.
Parameters:
*cols¶ – series of columns, SQL expressions, or whole tables
entities to be returned.
sort_by_parameter_order¶ – 
for a batch INSERT that is being
executed against multiple parameter sets, organize the results of
RETURNING so that the returned rows correspond to the order of
parameter sets passed in.  This applies only to an executemany
execution for supporting dialects and typically makes use of the
insertmanyvalues feature.
New in version 2.0.10.
See also
Correlating RETURNING rows to parameter sets - background on
sorting of RETURNING rows for bulk INSERT (Core level discussion)
Correlating RETURNING records with input data order - example of
use with ORM Bulk INSERT Statements (ORM level discussion)
See also
UpdateBase.return_defaults() - an alternative method tailored
towards efficient fetching of server-side defaults and triggers
for single-row INSERTs or UPDATEs.
INSERT…RETURNING - in the SQLAlchemy Unified Tutorial
class sqlalchemy.sql.expression.Insert¶
Represent an INSERT construct.
The Insert object is created using the
insert() function.
Members
values(), returning(), from_select(), inline(), select
Class signature
class sqlalchemy.sql.expression.Insert (sqlalchemy.sql.expression.ValuesBase)
method sqlalchemy.sql.expression.Insert.values(*args: _DMLColumnKeyMapping[Any] | Sequence[Any], **kwargs: Any) → Self¶
inherited from the ValuesBase.values() method of ValuesBase
Specify a fixed VALUES clause for an INSERT statement, or the SET
clause for an UPDATE.
Note that the Insert and
Update
constructs support
per-execution time formatting of the VALUES and/or SET clauses,
based on the arguments passed to Connection.execute().
However, the ValuesBase.values() method can be used to “fix” a
particular set of parameters into the statement.
Multiple calls to ValuesBase.values() will produce a new
construct, each one with the parameter list modified to include
the new parameters sent.  In the typical case of a single
dictionary of parameters, the newly passed keys will replace
the same keys in the previous construct.  In the case of a list-based
“multiple values” construct, each new list of values is extended
onto the existing list of values.
Parameters:
**kwargs¶ – 
key value pairs representing the string key
of a Column
mapped to the value to be rendered into the
VALUES or SET clause:
users.insert().values(name="some name")
users.update().where(users.c.id==5).values(name="some name")




    

*args¶ – 
As an alternative to passing key/value parameters,
a dictionary, tuple, or list of dictionaries or tuples can be passed
as a single positional argument in order to form the VALUES or
SET clause of the statement.  The forms that are accepted vary
based on whether this is an Insert or an
Update construct.
For either an Insert or
Update
construct, a single dictionary can be passed, which works the same as
that of the kwargs form:
users.insert().values({"name": "some name"})
users.update().values({"name": "some new name"})
Also for either form but more typically for the
Insert construct, a tuple that contains an
entry for every column in the table is also accepted:
users.insert().values((5, "some name"))
The Insert construct also supports being
passed a list of dictionaries or full-table-tuples, which on the
server will render the less common SQL syntax of “multiple values” -
this syntax is supported on backends such as SQLite, PostgreSQL,
MySQL, but not necessarily others:
users.insert().values([
                    {"name": "some name"},
                    {"name": "some other name"},
                    {"name": "yet another name"},
The above form would render a multiple VALUES statement similar to:
INSERT INTO users (name) VALUES
                (:name_1),
                (:name_2),
                (:name_3)
It is essential to note that passing multiple values is
NOT the same as using traditional executemany() form.  The above
syntax is a special syntax not typically used.  To emit an
INSERT statement against multiple rows, the normal method is
to pass a multiple values list to the
Connection.execute()
method, which is supported by all database backends and is generally
more efficient for a very large number of parameters.
See also
Sending Multiple Parameters - an introduction to
the traditional Core method of multiple parameter set
invocation for INSERTs and other statements.
The UPDATE construct also supports rendering the SET parameters
in a specific order.  For this feature refer to the
Update.ordered_values() method.
See also
Update.ordered_values()
method sqlalchemy.sql.expression.Insert.returning(*cols: _ColumnsClauseArgument[Any], sort_by_parameter_order: bool = False, **_UpdateBase__kw: Any) → UpdateBase¶
inherited from the UpdateBase.returning() method of UpdateBase
Add a RETURNING or equivalent clause to this statement.
e.g.:
>>> stmt = (
...     table.update()
...     .where(table.c.data == "value")
...     .values(status="X")
...     .returning(table.c.server_flag, table.c.updated_timestamp)
... )
>>> print(stmt)
UPDATE some_table SET status=:status
WHERE some_table.data = :data_1
RETURNING some_table.server_flag, some_table.updated_timestamp
The method may be invoked multiple times to add new entries to the
list of expressions to be returned.
New in version 1.4.0b2: The method may be invoked multiple times to
add new entries to the list of expressions to be returned.
The given collection of column expressions should be derived from the
table that is the target of the INSERT, UPDATE, or DELETE.  While
Column objects are typical, the elements can also be
expressions:
>>> stmt = table.insert().returning(
...     (table.c.first_name + " " + table.c.last_name).label("fullname")
... )
>>> print(stmt)
INSERT INTO some_table (first_name, last_name)
VALUES (:first_name, :last_name)
RETURNING some_table.first_name || :first_name_1 || some_table.last_name AS fullname
Upon compilation, a RETURNING clause, or database equivalent,
will be rendered within the statement.   For INSERT and UPDATE,
the values are the newly inserted/updated values.  For DELETE,
the values are those of the rows which were deleted.
Upon execution, the values of the columns to be returned are made
available via the result set and can be iterated using
CursorResult.fetchone() and similar.
For DBAPIs which do not
natively support returning values (i.e. cx_oracle), SQLAlchemy will
approximate this behavior at the result level so that a reasonable
amount of behavioral neutrality is provided.
Note that not all databases/DBAPIs
support RETURNING.   For those backends with no support,
an exception is raised upon compilation and/or execution.
For those who do support it, the functionality across backends
varies greatly, including restrictions on executemany()
and other statements which return multiple rows. Please
read the documentation notes for the database in use in
order to determine the availability of RETURNING.
Parameters:
*cols¶ – series of columns, SQL expressions, or whole tables
entities to be returned.
sort_by_parameter_order¶ – 
for a batch INSERT that is being
executed against multiple parameter sets, organize the results of
RETURNING so that the returned rows correspond to the order of
parameter sets passed in.  This applies only to an executemany
execution for supporting dialects and typically makes use of the
insertmanyvalues feature.
New in version 2.0.10.
See also
Correlating RETURNING rows to parameter sets - background on
sorting of RETURNING rows for bulk INSERT (Core level discussion)
Correlating RETURNING records with input data order - example of
use with ORM Bulk INSERT Statements (ORM level discussion)
See also
UpdateBase.return_defaults() - an alternative method tailored
towards efficient fetching of server-side defaults and triggers
for single-row INSERTs or UPDATEs.
INSERT…RETURNING - in the SQLAlchemy Unified Tutorial
method sqlalchemy.sql.expression.Insert.from_select(names: Sequence[_DMLColumnArgument], select: Selectable, include_defaults: bool = True) → Self¶
Return a new Insert construct which represents
an INSERT...FROM SELECT statement.
e.g.:
sel = select(table1.c.a, table1.c.b).where(table1.c.c > 5)
ins = table2.insert().from_select(['a', 'b'], sel)




    

Parameters:
names¶ – a sequence of string column names or
Column
objects representing the target columns.
select¶ – a select() construct,
FromClause
or other construct which resolves into a
FromClause,
such as an ORM Query object, etc.  The order of
columns returned from this FROM clause should correspond to the
order of columns sent as the names parameter;  while this
is not checked before passing along to the database, the database
would normally raise an exception if these column lists don’t
correspond.
include_defaults¶ – 
if True, non-server default values and
SQL expressions as specified on Column objects
(as documented in Column INSERT/UPDATE Defaults) not
otherwise specified in the list of names will be rendered
into the INSERT and SELECT statements, so that these values are also
included in the data to be inserted.
A Python-side default that uses a Python callable function
will only be invoked once for the whole statement, and not
per row.
method sqlalchemy.sql.expression.Insert.inline() → Self¶
Make this Insert construct “inline” .
When set, no attempt will be made to retrieve the
SQL-generated default values to be provided within the statement;
in particular,
this allows SQL expressions to be rendered ‘inline’ within the
statement without the need to pre-execute them beforehand; for
backends that support “returning”, this turns off the “implicit
returning” feature for the statement.
Changed in version 1.4: the Insert.inline
parameter
is now superseded by the Insert.inline() method.
attribute sqlalchemy.sql.expression.Insert.select: Select[Any] | None = None¶
SELECT statement for INSERT .. FROM SELECT




    

class sqlalchemy.sql.expression.Update¶
Represent an Update construct.
The Update object is created using the
update() function.
Members
returning(), where(), values(), inline(), ordered_values()
Class signature
class sqlalchemy.sql.expression.Update (sqlalchemy.sql.expression.DMLWhereBase, sqlalchemy.sql.expression.ValuesBase)
method sqlalchemy.sql.expression.Update.returning(*cols: _ColumnsClauseArgument[Any], sort_by_parameter_order: bool = False, **_UpdateBase__kw: Any) → UpdateBase¶
inherited from the UpdateBase.returning() method of UpdateBase
Add a RETURNING or equivalent clause to this statement.
e.g.:
>>> stmt = (
...     table.update()
...     .where(table.c.data == "value")
...     .values(status="X")
...     .returning(table.c.server_flag, table.c.updated_timestamp)
... )
>>> print(stmt)
UPDATE some_table SET status=:status
WHERE some_table.data = :data_1
RETURNING some_table.server_flag, some_table.updated_timestamp
The method may be invoked multiple times to add new entries to the
list of expressions to be returned.
New in version 1.4.0b2: The method may be invoked multiple times to
add new entries to the list of expressions to be returned.
The given collection of column expressions should be derived from the
table that is the target of the INSERT, UPDATE, or DELETE.  While
Column objects are typical, the elements can also be
expressions:
>>> stmt = table.insert().returning(
...     (table.c.first_name + " " + table.c.last_name).label("fullname")
... )
>>> print(stmt)
INSERT INTO some_table (first_name, last_name)
VALUES (:first_name, :last_name)
RETURNING some_table.first_name || :first_name_1 || some_table.last_name AS fullname
Upon compilation, a RETURNING clause, or database equivalent,
will be rendered within the statement.   For INSERT and UPDATE,
the values are the newly inserted/updated values.  For DELETE,
the values are those of the rows which were deleted.
Upon execution, the values of the columns to be returned are made
available via the result set and can be iterated using
CursorResult.fetchone() and similar.
For DBAPIs which do not
natively support returning values (i.e. cx_oracle), SQLAlchemy will
approximate this behavior at the result level so that a reasonable
amount of behavioral neutrality is provided.
Note that not all databases/DBAPIs
support RETURNING.   For those backends with no support,
an exception is raised upon compilation and/or execution.
For those who do support it, the functionality across backends
varies greatly, including restrictions on executemany()
and other statements which return multiple rows. Please
read the documentation notes for the database in use in
order to determine the availability of RETURNING.
Parameters:
*cols¶ – series of columns, SQL expressions, or whole tables
entities to be returned.
sort_by_parameter_order¶ – 
for a batch INSERT that is being
executed against multiple parameter sets, organize the results of
RETURNING so that the returned rows correspond to the order of
parameter sets passed in.  This applies only to an executemany
execution for supporting dialects and typically makes use of the
insertmanyvalues feature.
New in version 2.0.10.
See also
Correlating RETURNING rows to parameter sets - background on
sorting of RETURNING rows for bulk INSERT (Core level discussion)
Correlating RETURNING records with input data order - example of
use with ORM Bulk INSERT Statements (ORM level discussion)
See also
UpdateBase.return_defaults() - an alternative method tailored
towards efficient fetching of server-side defaults and triggers
for single-row INSERTs or UPDATEs.
INSERT…RETURNING - in the SQLAlchemy Unified Tutorial
method sqlalchemy.sql.expression.Update.where(*whereclause: _ColumnExpressionArgument[bool]) → Self¶
inherited from the DMLWhereBase.where() method of DMLWhereBase
Return a new construct with the given expression(s) added to
its WHERE clause, joined to the existing clause via AND, if any.
Both Update.where() and Delete.where()
support multiple-table forms, including database-specific
UPDATE...FROM as well as DELETE..USING.  For backends that
don’t have multiple-table support, a backend agnostic approach
to using multiple tables is to make use of correlated subqueries.
See the linked tutorial sections below for examples.
See also
Correlated Updates
UPDATE..FROM
Multiple Table Deletes
method sqlalchemy.sql.expression.Update.values(*args: _DMLColumnKeyMapping[Any] | Sequence[Any], **kwargs: Any) → Self¶
inherited from the ValuesBase.values() method of ValuesBase
Specify a fixed VALUES clause for an INSERT statement, or the SET
clause for an UPDATE.
Note that the Insert and
Update
constructs support
per-execution time formatting of the VALUES and/or SET clauses,
based on the arguments passed to Connection.execute().
However, the ValuesBase.values() method can be used to “fix” a
particular set of parameters into the statement.
Multiple calls to ValuesBase.values() will produce a new
construct, each one with the parameter list modified to include
the new parameters sent.  In the typical case of a single
dictionary of parameters, the newly passed keys will replace
the same keys in the previous construct.  In the case of a list-based
“multiple values” construct, each new list of values is extended
onto the existing list of values.
Parameters:
**kwargs¶ – 
key value pairs representing the string key
of a Column
mapped to the value to be rendered into the
VALUES or SET clause:
users.insert().values(name="some name")
users.update().where(users.c.id==5).values(name="some name")




    

*args¶ – 
As an alternative to passing key/value parameters,
a dictionary, tuple, or list of dictionaries or tuples can be passed
as a single positional argument in order to form the VALUES or
SET clause of the statement.  The forms that are accepted vary
based on whether this is an Insert or an
Update construct.
For either an Insert or
Update
construct, a single dictionary can be passed, which works the same as
that of the kwargs form:
users.insert().values({"name": "some name"})
users.update().values({"name": "some new name"})
Also for either form but more typically for the
Insert construct, a tuple that contains an
entry for every column in the table is also accepted:
users.insert().values((5, "some name"))
The Insert construct also supports being
passed a list of dictionaries or full-table-tuples, which on the
server will render the less common SQL syntax of “multiple values” -
this syntax is supported on backends such as SQLite, PostgreSQL,
MySQL, but not necessarily others:
users.insert().values([
                    {"name": "some name"},
                    {"name": "some other name"},
                    {"name": "yet another name"},
The above form would render a multiple VALUES statement similar to:
INSERT INTO users (name) VALUES
                (:name_1),
                (:name_2),
                (:name_3)
It is essential to note that passing multiple values is
NOT the same as using traditional executemany() form.  The above
syntax is a special syntax not typically used.  To emit an
INSERT statement against multiple rows, the normal method is
to pass a multiple values list to the
Connection.execute()
method, which is supported by all database backends and is generally
more efficient for a very large number of parameters.
See also
Sending Multiple Parameters - an introduction to
the traditional Core method of multiple parameter set
invocation for INSERTs and other statements.
The UPDATE construct also supports rendering the SET parameters
in a specific order.  For this feature refer to the
Update.ordered_values() method.
See also
Update.ordered_values()
method sqlalchemy.sql.expression.Update.inline() → Self¶
Make this Update construct “inline” .
When set, SQL defaults present on Column
objects via the
default keyword will be compiled ‘inline’ into the statement and
not pre-executed.  This means that their values will not be available
in the dictionary returned from
CursorResult.last_updated_params().
Changed in version 1.4: the update.inline
parameter
is now superseded by the Update.inline() method.
method sqlalchemy.sql.expression.Update.ordered_values(*args: Tuple[_DMLColumnArgument, Any]) → Self¶
Specify the VALUES clause of this UPDATE statement with an explicit
parameter ordering that will be maintained in the SET clause of the
resulting UPDATE statement.
E.g.:
stmt = table.update().ordered_values(
    ("name", "ed"), ("ident", "foo")
See also
Parameter Ordered Updates - full example of the
Update.ordered_values() method.
Changed in version 1.4: The Update.ordered_values()
method
supersedes the
update.preserve_parameter_order
parameter, which will be removed in SQLAlchemy 2.0.
class sqlalchemy.sql.expression.UpdateBase¶
Form the base for INSERT, UPDATE, and DELETE statements.
Members
entity_description, exported_columns, params(), return_defaults(), returning(), returning_column_descriptions, with_dialect_options(), with_hint()
Class signature
class sqlalchemy.sql.expression.UpdateBase (sqlalchemy.sql.roles.DMLRole, sqlalchemy.sql.expression.HasCTE, sqlalchemy.sql.expression.HasCompileState, sqlalchemy.sql.base.DialectKWArgs, sqlalchemy.sql.expression.HasPrefixes, sqlalchemy.sql.expression.Generative, sqlalchemy.sql.expression.ExecutableReturnsRows, sqlalchemy.sql.expression.ClauseElement)
attribute sqlalchemy.sql.expression.UpdateBase.entity_description¶
Return a plugin-enabled description of the table and/or
entity which this DML construct is operating against.
This attribute is generally useful when using the ORM, as an
extended structure which includes information about mapped
entities is returned.  The section Inspecting entities and columns from ORM-enabled SELECT and DML statements
contains more background.
For a Core statement, the structure returned by this accessor
is derived from the UpdateBase.table attribute, and
refers to the Table being inserted, updated, or deleted:
>>> stmt = insert(user_table)
>>> stmt.entity_description
    "name": "user_table",
    "table": Table("user_table", ...)
New in version 1.4.33.
See also
UpdateBase.returning_column_descriptions
Select.column_descriptions - entity information for
a select() construct
Inspecting entities and columns from ORM-enabled SELECT and DML statements - ORM background
attribute sqlalchemy.sql.expression.UpdateBase.exported_columns¶
Return the RETURNING columns as a column collection for this
statement.
New in version 1.4.
method sqlalchemy.sql.expression.UpdateBase.params(*arg: Any, **kw: Any) → NoReturn¶
Set the parameters for the statement.
This method raises NotImplementedError on the base class,
and is overridden by ValuesBase to provide the
SET/VALUES clause of UPDATE and INSERT.
method sqlalchemy.sql.expression.UpdateBase.return_defaults(*cols: _DMLColumnArgument, supplemental_cols: Iterable[_DMLColumnArgument] | None = None, sort_by_parameter_order: bool = False) → Self¶
Make use of a RETURNING clause for the purpose
of fetching server-side expressions and defaults, for supporting
backends only.
Deep Alchemy
The UpdateBase.return_defaults() method is used by the ORM
for its internal work in fetching newly generated primary key
and server default values, in particular to provide the underyling
implementation of the Mapper.eager_defaults
ORM feature as well as to allow RETURNING support with bulk
ORM inserts.  Its behavior is fairly idiosyncratic
and is not really intended for general use.  End users should
stick with using UpdateBase.returning() in order to
add RETURNING clauses to their INSERT, UPDATE and DELETE
statements.
Normally, a single row INSERT statement will automatically populate the
CursorResult.inserted_primary_key attribute when executed,
which stores the primary key of the row that was just inserted in the
form of a Row object with column names as named tuple keys
(and the Row._mapping view fully populated as well). The
dialect in use chooses the strategy to use in order to populate this
data; if it was generated using server-side defaults and / or SQL
expressions, dialect-specific approaches such as cursor.lastrowid
or RETURNING are typically used to acquire the new primary key
value.
However, when the statement is modified by calling
UpdateBase.return_defaults() before executing the statement,
additional behaviors take place only for backends that support
RETURNING and for Table objects that maintain the
Table.implicit_returning parameter at its default value of
True. In these cases, when the CursorResult is returned
from the statement’s execution, not only will
CursorResult.inserted_primary_key be populated as always, the
CursorResult.returned_defaults attribute will also be
populated with a Row named-tuple representing the full range
of server generated
values from that single row, including values for any columns that
specify Column.server_default or which make use of
Column.default using a SQL expression.
When invoking INSERT statements with multiple rows using
insertmanyvalues, the
UpdateBase.return_defaults() modifier will have the effect of
the CursorResult.inserted_primary_key_rows and
CursorResult.returned_defaults_rows attributes being
fully populated with lists of Row objects representing newly
inserted primary key values as well as newly inserted server generated
values for each row inserted. The
CursorResult.inserted_primary_key and
CursorResult.returned_defaults attributes will also continue
to be populated with the first row of these two collections.
If the backend does not support RETURNING or the Table in use
has disabled Table.implicit_returning, then no RETURNING
clause is added and no additional data is fetched, however the
INSERT, UPDATE or DELETE statement proceeds normally.
E.g.:
stmt = table.insert().values(data='newdata').return_defaults()
result = connection.execute(stmt)
server_created_at = result.returned_defaults['created_at']




    

When used against an UPDATE statement
UpdateBase.return_defaults() instead looks for columns that
include Column.onupdate or
Column.server_onupdate parameters assigned, when
constructing the columns that will be included in the RETURNING clause
by default if explicit columns were not specified. When used against a
DELETE statement, no columns are included in RETURNING by default, they
instead must be specified explicitly as there are no columns that
normally change values when a DELETE statement proceeds.
New in version 2.0: UpdateBase.return_defaults() is supported
for DELETE statements also and has been moved from
ValuesBase to UpdateBase.




    

The UpdateBase.return_defaults() method is mutually exclusive
against the UpdateBase.returning() method and errors will be
raised during the SQL compilation process if both are used at the same
time on one statement. The RETURNING clause of the INSERT, UPDATE or
DELETE statement is therefore controlled by only one of these methods
at a time.
The UpdateBase.return_defaults() method differs from
UpdateBase.returning() in these ways:
UpdateBase.return_defaults() method causes the
CursorResult.returned_defaults collection to be populated
with the first row from the RETURNING result. This attribute is not
populated when using UpdateBase.returning().
UpdateBase.return_defaults() is compatible with existing
logic used to fetch auto-generated primary key values that are then
populated into the CursorResult.inserted_primary_key
attribute. By contrast, using UpdateBase.returning() will
have the effect of the CursorResult.inserted_primary_key
attribute being left unpopulated.
UpdateBase.return_defaults() can be called against any
backend. Backends that don’t support RETURNING will skip the usage
of the feature, rather than raising an exception, unless
supplemental_cols is passed. The return value
of CursorResult.returned_defaults will be None
for backends that don’t support RETURNING or for which the target
Table sets Table.implicit_returning to
False.
An INSERT statement invoked with executemany() is supported if the
backend database driver supports the
insertmanyvalues
feature which is now supported by most SQLAlchemy-included backends.
When executemany is used, the
CursorResult.returned_defaults_rows and
CursorResult.inserted_primary_key_rows accessors
will return the inserted defaults and primary keys.
New in version 1.4: Added
CursorResult.returned_defaults_rows and
CursorResult.inserted_primary_key_rows accessors.
In version 2.0, the underlying implementation which fetches and
populates the data for these attributes was generalized to be
supported by most backends, whereas in 1.4 they were only
supported by the psycopg2 driver.
cols¶ – optional list of column key names or
Column that acts as a filter for those columns that
will be fetched.
supplemental_cols¶ – 
optional list of RETURNING expressions,
in the same form as one would pass to the
UpdateBase.returning() method. When present, the additional
columns will be included in the RETURNING clause, and the
CursorResult object will be “rewound” when returned, so
that methods like CursorResult.all() will return new rows
mostly as though the statement used UpdateBase.returning()
directly. However, unlike when using UpdateBase.returning()
directly, the order of the columns is undefined, so can only be
targeted using names or Row._mapping keys; they cannot
reliably be targeted positionally.
New in version 2.0.
sort_by_parameter_order¶ – 
for a batch INSERT that is being
executed against multiple parameter sets, organize the results of
RETURNING so that the returned rows correspond to the order of
parameter sets passed in.  This applies only to an executemany
execution for supporting dialects and typically makes use of the
insertmanyvalues feature.
New in version 2.0.10.
See also
Correlating RETURNING rows to parameter sets - background on
sorting of RETURNING rows for bulk INSERT
CursorResult.returned_defaults
CursorResult.returned_defaults_rows
CursorResult.inserted_primary_key
CursorResult.inserted_primary_key_rows
method sqlalchemy.sql.expression.UpdateBase.returning(*cols: _ColumnsClauseArgument[Any], sort_by_parameter_order: bool = False, **_UpdateBase__kw: Any) → UpdateBase¶
Add a RETURNING or equivalent clause to this statement.
e.g.:
>>> stmt = (
...     table.update()
...     .where(table.c.data == "value")
...     .values(status="X")
...     .returning(table.c.server_flag, table.c.updated_timestamp)
... )
>>> print(stmt)
UPDATE some_table SET status=:status
WHERE some_table.data = :data_1
RETURNING some_table.server_flag, some_table.updated_timestamp
The method may be invoked multiple times to add new entries to the
list of expressions to be returned.
New in version 1.4.0b2: The method may be invoked multiple times to
add new entries to the list of expressions to be returned.
The given collection of column expressions should be derived from the
table that is the target of the INSERT, UPDATE, or DELETE.  While
Column objects are typical, the elements can also be
expressions:
>>> stmt = table.insert().returning(
...     (table.c.first_name + " " + table.c.last_name).label("fullname")
... )
>>> print(stmt)
INSERT INTO some_table (first_name, last_name)
VALUES (:first_name, :last_name)
RETURNING some_table.first_name || :first_name_1 || some_table.last_name AS fullname
Upon compilation, a RETURNING clause, or database equivalent,
will be rendered within the statement.   For INSERT and UPDATE,
the values are the newly inserted/updated values.  For DELETE,
the values are those of the rows which were deleted.
Upon execution, the values of the columns to be returned are made
available via the result set and can be iterated using
CursorResult.fetchone() and similar.
For DBAPIs which do not
natively support returning values (i.e. cx_oracle), SQLAlchemy will
approximate this behavior at the result level so that a reasonable
amount of behavioral neutrality is provided.
Note that not all databases/DBAPIs
support RETURNING.   For those backends with no support,
an exception is raised upon compilation and/or execution.
For those who do support it, the functionality across backends
varies greatly, including restrictions on executemany()
and other statements which return multiple rows. Please
read the documentation notes for the database in use in
order to determine the availability of RETURNING.
Parameters:
*cols¶ – series of columns, SQL expressions, or whole tables
entities to be returned.
sort_by_parameter_order¶ – 
for a batch INSERT that is being
executed against multiple parameter sets, organize the results of
RETURNING so that the returned rows correspond to the order of
parameter sets passed in.  This applies only to an executemany
execution for supporting dialects and typically makes use of the
insertmanyvalues feature.
New in version 2.0.10.
See also
Correlating RETURNING rows to parameter sets - background on
sorting of RETURNING rows for bulk INSERT (Core level discussion)
Correlating RETURNING records with input data order - example of
use with ORM Bulk INSERT Statements (ORM level discussion)
See also
UpdateBase.return_defaults() - an alternative method tailored
towards efficient fetching of server-side defaults and triggers
for single-row INSERTs or UPDATEs.
INSERT…RETURNING - in the SQLAlchemy Unified Tutorial
attribute sqlalchemy.sql.expression.UpdateBase.returning_column_descriptions¶
Return a plugin-enabled description of the columns
which this DML construct is RETURNING against, in other words
the expressions established as part of UpdateBase.returning().
This attribute is generally useful when using the ORM, as an
extended structure which includes information about mapped
entities is returned.  The section Inspecting entities and columns from ORM-enabled SELECT and DML statements
contains more background.
For a Core statement, the structure returned by this accessor is
derived from the same objects that are returned by the
UpdateBase.exported_columns accessor:
>>> stmt = insert(user_table).returning(user_table.c.id, user_table.c.name)
>>> stmt.entity_description
        "name": "id",
        "type": Integer,
        "expr": Column("id", Integer(), table=<user>, ...)
        "name": "name",
        "type": String(),
        "expr": Column("name", String(), table=<user>, ...)
New in version 1.4.33.
See also
UpdateBase.entity_description
Select.column_descriptions - entity information for
a select() construct
Inspecting entities and columns from ORM-enabled SELECT and DML statements - ORM background
method sqlalchemy.sql.expression.UpdateBase.with_dialect_options(**opt: Any) → Self¶
Add dialect options to this INSERT/UPDATE/DELETE object.
e.g.:
upd = table.update().dialect_options(mysql_limit=10)




    

method sqlalchemy.sql.expression.UpdateBase.with_hint(text: str, selectable: _DMLTableArgument | None = None, dialect_name: str = '*') → Self¶
Add a table hint for a single table to this
INSERT/UPDATE/DELETE statement.
UpdateBase.with_hint() currently applies only to
Microsoft SQL Server.  For MySQL INSERT/UPDATE/DELETE hints, use
UpdateBase.prefix_with().
The text of the hint is rendered in the appropriate
location for the database backend in use, relative
to the Table that is the subject of this
statement, or optionally to that of the given
Table passed as the selectable argument.
The dialect_name option will limit the rendering of a particular
hint to a particular backend. Such as, to add a hint
that only takes effect for SQL Server:
mytable.insert().with_hint("WITH (PAGLOCK)", dialect_name="mssql")
Parameters:
text¶ – Text of the hint.
selectable¶ – optional Table that specifies
an element of the FROM clause within an UPDATE or DELETE
to be the subject of the hint - applies only to certain backends.
dialect_name¶ – defaults to *, if specified as the name
of a particular dialect, will apply these hints only when
that dialect is in use.
class sqlalchemy.sql.expression.ValuesBase¶
Supplies support for ValuesBase.values() to
INSERT and UPDATE constructs.
Members
select, values()
Class signature
class sqlalchemy.sql.expression.ValuesBase (sqlalchemy.sql.expression.UpdateBase)
attribute sqlalchemy.sql.expression.ValuesBase.select: Select[Any] | None = None¶
SELECT statement for INSERT .. FROM SELECT
method sqlalchemy.sql.expression.ValuesBase.values(*args: _DMLColumnKeyMapping[Any] | Sequence[Any], **kwargs: Any) → Self¶
Specify a fixed VALUES clause for an INSERT statement, or the SET
clause for an UPDATE.
Note that the Insert and
Update
constructs support
per-execution time formatting of the VALUES and/or SET clauses,
based on the arguments passed to Connection.execute().
However, the ValuesBase.values() method can be used to “fix” a
particular set of parameters into the statement.
Multiple calls to ValuesBase.values() will produce a new
construct, each one with the parameter list modified to include
the new parameters sent.  In the typical case of a single
dictionary of parameters, the newly passed keys will replace
the same keys in the previous construct.  In the case of a list-based
“multiple values” construct, each new list of values is extended
onto the existing list of values.
Parameters:
**kwargs¶ – 
key value pairs representing the string key
of a Column
mapped to the value to be rendered into the
VALUES or SET clause:
users.insert().values(name="some name")
users.update().where(users.c.id==5).values(name="some name")
*args¶ – 
As an alternative to passing key/value parameters,
a dictionary, tuple, or list of dictionaries or tuples can be passed
as a single positional argument in order to form the VALUES or
SET clause of the statement.  The forms that are accepted vary
based on whether this is an Insert or an
Update construct.
For either an Insert or
Update
construct, a single dictionary can be passed, which works the same as
that of the kwargs form:
users.insert().values({"name": "some name"})
users.update().values({"name": "some new name"})
Also for either form but more typically for the
Insert construct, a tuple that contains an
entry for every column in the table is also accepted:
users.insert().values((5, "some name"))
The Insert construct also supports being
passed a list of dictionaries or full-table-tuples, which on the
server will render the less common SQL syntax of “multiple values” -
this syntax is supported on backends such as SQLite, PostgreSQL,
MySQL, but not necessarily others:
users.insert().values([
                    {"name": "some name"},
                    {"name": "some other name"},
                    {"name": "yet another name"},
The above form would render a multiple VALUES statement similar to:
INSERT INTO users (name) VALUES
                (:name_1),
                (:name_2),
                (:name_3)
It is essential to note that passing multiple values is
NOT the same as using traditional executemany() form.  The above
syntax is a special syntax not typically used.  To emit an
INSERT statement against multiple rows, the normal method is
to pass a multiple values list to the
Connection.execute()
method, which is supported by all database backends and is generally
more efficient for a very large number of parameters.
See also
Sending Multiple Parameters - an introduction to
the traditional Core method of multiple parameter set
invocation for INSERTs and other statements.
The UPDATE construct also supports rendering the SET parameters
in a specific order.  For this feature refer to the
Update.ordered_values() method.
See also
Update.ordered_values()
    
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