sqlalchemy.sql.dml.UpdateBase

Undocumented

Undocumented

Undocumented

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.

Add a :term:`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.

The given collection of column expressions should be derived from the table that is the target of the INSERT, UPDATE, or DELETE. While _schema.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 _engine.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.

Add dialect options to this INSERT/UPDATE/DELETE object.

e.g.:

upd = table.update().dialect_options(mysql_limit=10)

Add a table hint for a single table to this INSERT/UPDATE/DELETE statement.

The text of the hint is rendered in the appropriate location for the database backend in use, relative to the _schema.Table that is the subject of this statement, or optionally to that of the given _schema.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")