Python MySQLdb更新查询失败

self.tbl.sql.use(self.tbl.database)       # switches to correct database. I've printed this and it uses the corrected db
if self.tbl.sql.execute(query) == True:
    print sql_obj.rows_affected()         # returns 1 (since i only do 1 query)

def execute(self, query):

    try:
        self.cursor.execute(query)
        return True
    except MySQLdb.ProgrammingError as error:
        print "---->SQL Error: %s" % error
        return False
    except MySQLdb.IntegrityError as e:
        print "--->SQL Error: %s" % e    
        return False