Function Connection.purgeResult

When the server responds to a command that produces a result set, it queues the whole set of corresponding packets over the current connection. Before that Connection can embark on any new command, it must receive all of those packets and junk them.

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//www.mysqlperformanceblog.com/2007/07/08/mysql-net_write_timeout-vs-wait_timeout-and-protocol-notes/