先上已经单独抽取出来的测试代码段，附运行结果，最后说明情况：

    from dbutils.pooled_db import PooledDB
    import pymysql

    sqlinfo = {'ip': '192.168.xx.xx',
               'port': 3306,
               'user': 'xxx',
               'password': 'xxx',
               'database': 'ppp',
               'charset': 'utf8'
               }

    POOL = PooledDB(
        creator=pymysql,  # 使用链接数据库的模块
        maxconnections=600,  # 连接池允许的最大连接数，0 和 None 表示不限制连接数
        mincached=2,  # 初始化时，链接池中至少创建的空闲的链接，0 表示不创建
        maxcached=5,  # 链接池中最多闲置的链接，0 和 None 不限制
        blocking=True,  # 连接池中如果没有可用连接后，是否阻塞等待。True ，等待； False ，不等待然后报错
        maxusage=None,  # 一个链接最多被重复使用的次数，None 表示无限制
        setsession=[],  # 开始会话前执行的命令列表。
        ping=1,  # ping MySQL 服务端，检查是否服务可用。
        host=sqlinfo['ip'],
        port=sqlinfo['port'],
        user=sqlinfo['user'],
        password=sqlinfo['password'],
        database=sqlinfo['database'],
        charset=sqlinfo['charset']
    )

    DBconn = POOL.connection()
    cur = DBconn.cursor()
    sqlCMDtext = "DELETE FROM `addmc` WHERE `mcid`='7981';DELETE FROM `mc` WHERE `mcid`='7981';"

    ret = cur.execute(sqlCMDtext)
    print(ret)
    DBconn.close()

报错提示：

Traceback (most recent call last):
  File "D:/test/test.py", line 46, in <module>
    ret = cur.execute(sqltext)
  File "C:\Users\Administrator\venv\lib\site-packages\dbutils\steady_db.py", line 598, in tough_method
    result = method(*args, **kwargs)  # try to execute
  File "C:\Users\Administrator\venv\lib\site-packages\pymysql\cursors.py", line 170, in execute
    result = self._query(query)
  File "C:\Users\Administrator\venv\lib\site-packages\pymysql\cursors.py", line 328, in _query
    conn.query(q)
  File "C:\Users\Administrator\venv\lib\site-packages\pymysql\connections.py", line 517, in query
    self._affected_rows = self._read_query_result(unbuffered=unbuffered)
  File "C:\Users\Administrator\venv\lib\site-packages\pymysql\connections.py", line 732, in _read_query_result
    result.read()
  File "C:\Users\Administrator\venv\lib\site-packages\pymysql\connections.py", line 1075, in read
    first_packet = self.connection._read_packet()
  File "C:\Users\Administrator\venv\lib\site-packages\pymysql\connections.py", line 684, in _read_packet
    packet.check_error()
  File "C:\Users\Administrator\venv\lib\site-packages\pymysql\protocol.py", line 220, in check_error
    err.raise_mysql_exception(self._data)
  File "C:\Users\Administrator\venv\lib\site-packages\pymysql\err.py", line 109, in raise_mysql_exception
    raise errorclass(errno, errval)
pymysql.err.ProgrammingError: (1064, "You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'DELETE FROM `mc` WHERE `mcid`='7981'' at line 1")

1 、莫关心 SQL 语句的目的实现，虽然一条语句就完成删除两张表的内容目标，但问题的本身：是为啥认不出第二条语句而报错？ 这个组装语句在 MySQL 执行没毛病
2 、用 thSQLconn = MySQLdb.connect()
thSQLCursor = thSQLconn.cursor thSQLCursor.execute(sqlCMDtext) 这种一般 MySQLdb 的执行方式，组装的 SQL 妥妥没毛病。
3 、因为是在多线程环境，sqlCMDtext 是来自于 SQLQueue = multiprocessing.Manager.Queue()队列,SQLQueue.get()获得，在多线程里共享队列，PooledDB+队列，目前这个方式处理生产消费模型，PooledDB 支持多线程，也能在共享队列里取到 SQL 语句，所以我也没找其它的方式。。。
4 、PooledDB 为啥不能处理这个的 SQL 语句呢？