mysql_thread_id Return the current thread ID intmysql_thread_id resourcelink_identifier mysql_thread_id returns the current thread ID. If the connection is lost and you reconnect with mysql_ping, the thread ID will change. This means you should not get the thread ID and store it for later. You should get it when you need it. ]]> The above example would produce the following output: See also mysql_ping and mysql_list_processes.