Class Select

lib/sqlalchemy/sql/selectable.py:5449–7033

Represents a ``SELECT`` statement. The :class:`_sql.Select` object is normally constructed using the :func:`_sql.select` function. See that function for details. Available extension points: * ``post_select``: applies additional logic after the ``SELECT`` keyword. * ``pre_colu

class Select(
    HasPrefixes,
    HasSuffixes,
    HasHints,
    HasCompileState,
    HasSyntaxExtensions[
        Literal["post_select", "pre_columns", "post_criteria", "post_body"]
    ],
    _SelectFromElements,
    GenerativeSelect,
    TypedReturnsRows[Unpack[_Ts]],
):
    """Represents a ``SELECT`` statement.

    The :class:`_sql.Select` object is normally constructed using the
    :func:`_sql.select` function.  See that function for details.

    Available extension points:

    * ``post_select``: applies additional logic after the ``SELECT`` keyword.
    * ``pre_columns``: applies additional logic between the ``DISTINCT``
        keyword (if any) and the list of columns.
    * ``post_criteria``: applies additional logic after the ``HAVING`` clause.
    * ``post_body``: applies additional logic after the ``FOR UPDATE`` clause.

    .. seealso::

        :func:`_sql.select`

        :ref:`tutorial_selecting_data` - in the 2.0 tutorial

    """

    __visit_name__ = "select"

    _setup_joins: Tuple[_SetupJoinsElement, ...] = ()
    _memoized_select_entities: Tuple[TODO_Any, ...] = ()

    _raw_columns: List[_ColumnsClauseElement]

    _distinct: bool = False
    _distinct_on: Tuple[ColumnElement[Any], ...] = ()
    _correlate: Tuple[FromClause, ...] = ()
    _correlate_except: Optional[Tuple[FromClause, ...]] = None
    _where_criteria: Tuple[ColumnElement[Any], ...] = ()
    _having_criteria: Tuple[ColumnElement[Any], ...] = ()
    _from_obj: Tuple[FromClause, ...] = ()

    _position_map = util.immutabledict(
        {
            "post_select": "_post_select_clause",
            "pre_columns": "_pre_columns_clause",
            "post_criteria": "_post_criteria_clause",
            "post_body": "_post_body_clause",
        }
    )

    _post_select_clause: Optional[ClauseElement] = None