Method with_for_update

lib/sqlalchemy/sql/selectable.py:4114–4179

Specify a ``FOR UPDATE`` clause for this :class:`_expression.GenerativeSelect`. E.g.:: stmt = select(table).with_for_update(nowait=True) On a database like PostgreSQL or Oracle Database, the above would render a statement like: .. sourcecode::

(
        self,
        *,
        nowait: bool = False,
        read: bool = False,
        of: Optional[_ForUpdateOfArgument] = None,
        skip_locked: bool = False,
        key_share: bool = False,
    )

    @_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:
        """Specify a ``FOR UPDATE`` clause for this
        :class:`_expression.GenerativeSelect`.

        E.g.::

            stmt = select(table).with_for_update(nowait=True)

        On a database like PostgreSQL or Oracle Database, the above would
        render a statement like:

        .. sourcecode:: sql

            SELECT table.a, table.b FROM table FOR UPDATE NOWAIT

        on other backends, the ``nowait`` option is ignored and instead
        would produce:

        .. sourcecode:: sql

            SELECT table.a, table.b FROM table FOR UPDATE

        When called with no arguments, the statement will render with
        the suffix ``FOR UPDATE``.   Additional arguments can then be
        provided which allow for common database-specific
        variants.

        :param nowait: boolean; will render ``FOR UPDATE NOWAIT`` on Oracle
         Database and PostgreSQL dialects.

        :param read: boolean; will render ``LOCK IN SHARE MODE`` on MySQL,
         ``FOR SHARE`` on PostgreSQL.  On PostgreSQL, when combined with
         ``nowait``, will render ``FOR SHARE NOWAIT``.

        :param of: SQL expression or list of SQL expression elements,
         (typically :class:`_schema.Column` objects or a compatible expression,
         for some backends may also be a table expression) which will render
         into a ``FOR UPDATE OF`` clause; supported by PostgreSQL, Oracle
         Database, some MySQL versions and possibly others. May render as a
         table or as a column depending on backend.

        :param skip_locked: boolean, will render ``FOR UPDATE SKIP LOCKED`` on
         Oracle Database and PostgreSQL dialects or ``FOR SHARE SKIP LOCKED``
         if ``read=True`` is also specified.

        :param key_share: boolean, will render ``FOR NO KEY UPDATE``,
         or if combined with ``read=True`` will render ``FOR KEY SHARE``,
         on the PostgreSQL dialect.

        """