def get_pre_alter_table_index_foreign_key_sql(self, diff):
        """
        :param diff: The table diff
        :type diff: orator.dbal.table_diff.TableDiff

        :rtype: list
        """
        if not isinstance(diff.from_table, Table):
            raise DBALException(
                "Sqlite platform requires for alter table the table"
                "diff with reference to original table schema"
            )

        sql = []
        for index in diff.from_table.get_indexes().values():
            if not index.is_primary():
                sql.append(self.get_drop_index_sql(index, diff.name))

        return sql
def get_pre_alter_table_index_foreign_key_sql ( self , diff ) : if not isinstance ( diff . from_table , Table ) : raise DBALException ( "Sqlite platform requires for alter table the table" "diff with reference to original table schema" ) sql = [ ] for index in diff . from_table . get_indexes ( ) . values ( ) : if not index . is_primary ( ) : sql . append ( self . get_drop_index_sql ( index , diff . name ) ) return sql
:param diff: The table diff
        :type diff: orator.dbal.table_diff.TableDiff

        :rtype: list