app/django/db/backends/postgresql_psycopg2/introspection.py
author Sverre Rabbelier <srabbelier@gmail.com>
Mon, 03 Nov 2008 19:47:02 +0000
changeset 439 0658c3c9a9dc
parent 323 ff1a9aa48cfd
permissions -rw-r--r--
Minor fixes needed for generic key name We no longer try to retreive an entity when there are unset fields. This sort of makes 'getIfFields' obsolete, since we check if fields now anyway. This is needed because getKeyFieldsFromDict expects the fields to be set. Also a minor fix in a Django template so that the generic 'edit' page has a working delete button again.

from django.db.backends.postgresql.introspection import DatabaseIntrospection as PostgresDatabaseIntrospection

class DatabaseIntrospection(PostgresDatabaseIntrospection):

    def get_relations(self, cursor, table_name):
        """
        Returns a dictionary of {field_index: (field_index_other_table, other_table)}
        representing all relationships to the given table. Indexes are 0-based.
        """
        cursor.execute("""
            SELECT con.conkey, con.confkey, c2.relname
            FROM pg_constraint con, pg_class c1, pg_class c2
            WHERE c1.oid = con.conrelid
                AND c2.oid = con.confrelid
                AND c1.relname = %s
                AND con.contype = 'f'""", [table_name])
        relations = {}
        for row in cursor.fetchall():
            # row[0] and row[1] are single-item lists, so grab the single item.
            relations[row[0][0] - 1] = (row[1][0] - 1, row[2])
        return relations