Function _collect_delete_commands

lib/sqlalchemy/orm/persistence.py:694–729

Identify values to use in DELETE statements for a list of states to be deleted.

(
    base_mapper, uowtransaction, table, states_to_delete
)

def _collect_delete_commands(
    base_mapper, uowtransaction, table, states_to_delete
):
    """Identify values to use in DELETE statements for a list of
    states to be deleted."""

    for (
        state,
        state_dict,
        mapper,
        connection,
        update_version_id,
    ) in states_to_delete:
        if table not in mapper._pks_by_table:
            continue

        params = {}
        for col in mapper._pks_by_table[table]:
            params[col.key] = value = (
                mapper._get_committed_state_attr_by_column(
                    state, state_dict, col
                )
            )
            if value is None:
                raise orm_exc.FlushError(
                    "Can't delete from table %s "
                    "using NULL for primary "
                    "key value on column %s" % (table, col)
                )

        if (
            update_version_id is not None
            and mapper.version_id_col in mapper._cols_by_table[table]
        ):
            params[mapper.version_id_col.key] = update_version_id
        yield params, connection


def _emit_update_statements(