Method setup_query

lib/sqlalchemy/orm/strategies.py:2140–2266

Add a left outer join to the statement that's being constructed.

(
        self,
        compile_state,
        query_entity,
        path,
        loadopt,
        adapter,
        column_collection=None,
        parentmapper=None,
        chained_from_outerjoin=False,
        **kwargs,
    )

        ).init_class_attribute(mapper)

    def setup_query(
        self,
        compile_state,
        query_entity,
        path,
        loadopt,
        adapter,
        column_collection=None,
        parentmapper=None,
        chained_from_outerjoin=False,
        **kwargs,
    ):
        """Add a left outer join to the statement that's being constructed."""

        if not compile_state.compile_options._enable_eagerloads:
            return
        elif (
            loadopt
            and compile_state.statement is not None
            and compile_state.statement.is_dml
        ):
            util.warn_deprecated(
                "The joinedload loader option is not compatible with DML "
                "statements such as INSERT, UPDATE.  Only SELECT may be used."
                "This warning will become an exception in a future release.",
                "2.0",
            )
        elif self.uselist:
            compile_state.multi_row_eager_loaders = True

        path = path[self.parent_property]

        user_defined_adapter = (
            self._init_user_defined_eager_proc(
                loadopt, compile_state, compile_state.attributes
            )
            if loadopt
            else False
        )

        if user_defined_adapter is not False:
            # setup an adapter but dont create any JOIN, assume it's already
            # in the query
            (
                clauses,
                adapter,
                add_to_collection,
            ) = self._setup_query_on_user_defined_adapter(
                compile_state,
                query_entity,
                path,
                adapter,
                user_defined_adapter,
            )

            # don't do "wrap" for multi-row, we want to wrap
            # limited/distinct SELECT,
            # because we want to put the JOIN on the outside.