Can't use `mysqldiff` or `mysqlcompare`

[bravecorvus]

We are using AWS RDS MySQL version 5.6.10. I have installed mysql-utilities from https://github.com/mysql/mysql-utilities via the manual install method (python2 setup.py install) and the mysql-connector-python package from pip (pip install --user mysql-connector-python). We are trying to see the diff between the 2 databases

Since I am using Python2 and by extension, pip from Homebrew, I had to modify the script a little bit (using /usr/local/bin/python2 rather than /usr/bin/python).

For mysqldiff I am running the command:

mysqldiff \
  --server1='[username1]:[password1]@[servername1].rds.amazonaws.com:3306' \
  --server2='[username2]:[password2]@[servername2].rds.amazonaws.com:3306' \
  --difftype=differ \
  [databasename1]:[databasename2]

For mysqldbcompare, I am running the command:

mysqldbcompare \
  --server1='[username1]:[password1]@[servername1].rds.amazonaws.com:3306' \
  --server2='[username2]:[password2]@[servername2].rds.amazonaws.com:3306' \
  --difftype=differ \
  [databasename1]:[databasename2]

However, I am getting the following errors:

# WARNING: Using a password on the command line interface can be insecure.
Traceback (most recent call last):
  File "./src/mysqldbcompare", line 299, in <module>
    servers = connect_servers(server1_values, server2_values, conn_opts)
  File "/usr/local/lib/python2.7/site-packages/mysql/utilities/common/server.py", line 489, in connect_servers
    source = get_server(src_name, src_dict, quiet, verbose=verbose)
  File "/usr/local/lib/python2.7/site-packages/mysql/utilities/common/server.py", line 336, in get_server
    server_conn.connect()
  File "/usr/local/lib/python2.7/site-packages/mysql/utilities/common/server.py", line 1104, in connect
    res = self.show_server_variable('character_set_client')
  File "/usr/local/lib/python2.7/site-packages/mysql/utilities/common/server.py", line 1391, in show_server_variable
    return self.exec_query("SHOW VARIABLES LIKE '%s'" % variable)
  File "/usr/local/lib/python2.7/site-packages/mysql/utilities/common/server.py", line 1327, in exec_query
    cur.close()
  File "/usr/local/lib/python2.7/site-packages/mysql/connector/cursor.py", line 395, in close
    self._connection.handle_unread_result()
  File "/usr/local/lib/python2.7/site-packages/mysql/connector/connection_cext.py", line 614, in handle_unread_result
    raise errors.InternalError("Unread result found")
mysql.connector.errors.InternalError: Unread result found

Why I think this is a mysql-utilities error:

I tried manually connecting via mysql --host='[servername].rds.amazonaws.com' --user=[username] --password='[password]' --port=3306 and I was able to connect with no errors.

Further info:

MySQL Version: 5.6.10 AWS RDS
Python 2 Version: Python 2.7.15 (from macOS Homebrew)
mysql-utilities Version: 1.6.5
mysql-connector-python Version: 8.0.13

[bravecorvus]

*hears crickets

[mcouthon]

I've found the issue. Actually, there are 2 issues.
The first is that you need to set a character set by passing something like --character-set utf8 to the command. That's easy.
The second is the more problematic one, and is actually a problem with the connector, not the utilities.
The issue is due to this bit https://github.com/mysql/mysql-connector-python/blob/master/lib/mysql/connector/connection_cext.py#L514

I have a PR up on the mysql-connector-python repo with more technical details.

[bravecorvus]

Good stuff.