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Classe « FunctionElement »

Méthode sqlalchemy.FunctionElement.column_valued

Signature de la méthode column_valued

def column_valued(self, name: 'Optional[str]' = None, joins_implicitly: 'bool' = False) -> 'TableValuedColumn[_T]' 

Description

help(FunctionElement.column_valued)

Return this :class:`_functions.FunctionElement` as a column expression that
selects from itself as a FROM clause.

E.g.:

.. sourcecode:: pycon+sql

    >>> from sqlalchemy import select, func
    >>> gs = func.generate_series(1, 5, -1).column_valued()
    >>> print(select(gs))
    {printsql}SELECT anon_1
    FROM generate_series(:generate_series_1, :generate_series_2, :generate_series_3) AS anon_1

This is shorthand for::

    gs = func.generate_series(1, 5, -1).alias().column

:param name: optional name to assign to the alias name that's generated.
 If omitted, a unique anonymizing name is used.

:param joins_implicitly: when True, the "table" portion of the column
 valued function may be a member of the FROM clause without any
 explicit JOIN to other tables in the SQL query, and no "cartesian
 product" warning will be generated. May be useful for SQL functions
 such as ``func.json_array_elements()``.

 .. versionadded:: 1.4.46

.. seealso::

    :ref:`tutorial_functions_column_valued` - in the :ref:`unified_tutorial`

    :ref:`postgresql_column_valued` - in the :ref:`postgresql_toplevel` documentation

    :meth:`_functions.FunctionElement.table_valued`

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