Python MySQLdb处理多个游标:命令不同步

时间:2013-10-10 13:24:24

标签: python mysql cursor mysql-python

我有一个数据库连接方法,可以创建连接并将光标设置为 init 进程的一部分。

然后我有以下使用光标的方法:

def calculatePercentile(self):
    user_edits = ur'''SELECT /* SLOW_OK_LIMIT: 1800 */ user_id, user_editcount from user'''
    num_user_per_percentile = ur'''SELECT /* SLOW_OK_LIMIT: 1800 */ count(user_id) from user where user_editcount = %(count)s'''        
    lang_edit_count_dictionary = {}
    lang_edit_count_dictionary[self.language] = []
    edit_count_list = []
    p = [10, 20, 30, 40, 50, 60, 70, 80, 90, 95]
    bot_users = self._getBotUsers()
    success = False
    attempts = 0
    while attempts < 3 and not success:
        try:
            self.dbCursor.execute(user_edits)
            for user in self.dbCursor.fetchall():
                user_id = user['user_id']
                user_editcount = user['user_editcount']
                if user_id not in bot_users:
                    edit_count_list.append(user_editcount)
            edit_count_list.sort()
            for i in p:
                lang_edit_count_dictionary[self.language].append(np.percentile(edit_count_list, i))
            success = True
        except MySQLdb.OperationalError, sqlEx:
            attempts += 1
            if sqlEx[0] == 2006:
                logging.info("Caught the MySQL server gone away exception")
                logging.error(sqlEx)
                time.sleep(10)
                self.connectServer()
        except Exception, e:
            traceback.print_exc()
            logging.exception(e)
    for key, values in lang_edit_count_dictionary.iteritems():
        print key
        for value in values:
            self.dbCursor.execute(num_user_per_percentile, {"count":value})
            uEditCount = self.dbCursor.fetchone()
            print uEditCount

这个方法的作用是,它执行一个查询获取其数据并将该数据转储到,然后使用相同的游标在内部执行另一个查询:

for key, values in lang_edit_count_dictionary.iteritems():
    print key
    for value in values:
        self.dbCursor.execute(num_user_per_percentile, {"count":value})
        uEditCount = self.dbCursor.fetchone()
        print uEditCount

发生的是我收到以下错误:

    self.dbCursor.execute(num_user_per_percentile, {"count":value})
  File "/home/auduwage/code/vInterLang/local/lib/python2.7/site-packages/MySQLdb/cursors.py", line 201, in execute
    self.errorhandler(self, exc, value)
  File "/home/auduwage/code/vInterLang/local/lib/python2.7/site-packages/MySQLdb/connections.py", line 36, in defaulterrorhandler
    raise errorclass, errorvalue
_mysql_exceptions.ProgrammingError: (2014, "Commands out of sync; you can't run this command now")
Exception _mysql_exceptions.ProgrammingError: (2014, "Commands out of sync; you can't run this command now") in <bound method SSDictCursor.__del__ of <MySQLdb.cursors.SSDictCursor object at 0x2716ed0>> ignored

在此之前我在不同的方法中使用了相同的游标,我不认为这与MySql有关,不允许我使用相同的游标一个接一个地运行多个查询?或者是吗? 会有什么解决方案?

1 个答案:

答案 0 :(得分:3)

您无法运行复合sql语句。 你需要将它们分开。

这将返回该错误:

cursor.execute("drop database x; drop table y;")

这样可以正常工作:

cursor.execute("drop database x;")
cursor.execute("drop table y;")