今天clickhouse换了个服务器，从20.3.12换到版本19.16.19，发现之前脚本中使用的client api不能用了，报错如下

>>> client.execute('SHOW DATABASES')

Traceback (most recent call last):

  File "<stdin>", line 1, in <module>

  File "/usr/lib64/python2.7/site-packages/clickhouse_driver/client.py", line 205, in execute

    self.connection.force_connect()

  File "/usr/lib64/python2.7/site-packages/clickhouse_driver/connection.py", line 184, in force_connect

    self.connect()

  File "/usr/lib64/python2.7/site-packages/clickhouse_driver/connection.py", line 256, in connect

    return self._init_connection(host, port)

  File "/usr/lib64/python2.7/site-packages/clickhouse_driver/connection.py", line 238, in _init_connection

    self.receive_hello()

  File "/usr/lib64/python2.7/site-packages/clickhouse_driver/connection.py", line 331, in receive_hello

    packet_type = read_varint(self.fin)

  File "clickhouse_driver/varint.pyx", line 40, in clickhouse_driver.varint.read_varint

  File "clickhouse_driver/bufferedreader.pyx", line 55, in clickhouse_driver.bufferedreader.BufferedReader.read_one

  File "clickhouse_driver/bufferedreader.pyx", line 191, in clickhouse_driver.bufferedreader.BufferedSocketReader.read_into_buffer

EOFError: Unexpected EOF while reading bytes

>>>

网上无解，原因不知道。没办法去官方文档上翻一翻

https://clickhouse-driver.readthedocs.io/en/latest/dbapi.html#connection

发现可以使用另外一个api 连接数据库（DB API 2.0）---connect,可以规避这个问题

github上使用示例：

        https://github.com/mymarilyn/clickhouse-driver