708                         ' AND '.join(restrictions))

   708                         ' AND '.join(restrictions))

   709                 else:

   709                 else:

   710                     sql = 'NOT EXISTS(SELECT 1 FROM %s WHERE %s)' % (

   710                     sql = 'NOT EXISTS(SELECT 1 FROM %s WHERE %s)' % (

   711                         ', '.join(tables), ' AND '.join(restrictions))

   711                         ', '.join(tables), ' AND '.join(restrictions))

   712             else:

   712             else:

   714                 sql = '%s IS NULL' % self._inlined_var_sql(lhsvar, relation.r_type)

   713                 sql = '%s IS NULL' % self._inlined_var_sql(lhsvar, relation.r_type)

   715             return sql

   714             return sql

   716         lhssql = self._inlined_var_sql(lhsvar, relation.r_type)

   715         lhssql = self._inlined_var_sql(lhsvar, relation.r_type)

   717         if rhsconst is not None:

   716         if rhsconst is not None:

   718             return '%s=%s' % (lhssql, rhsconst.accept(self))

   717             return '%s=%s' % (lhssql, rhsconst.accept(self))