• Debug 

The thread is generating debugging information. 

• Delayed insert 

The thread is a delayed insert handler. 

• Drop DB 

The thread is executing a drop database operation. 

• Error 

• Execute 

The thread is executing a prepared statement. 

• Fetch 

The thread is fetching the results from executing a prepared statement. 

• Field List 

The thread is retrieving information for table columns. 

• Init DB 

The thread is selecting a default database. 

• Kill 

The thread is killing another thread. 

• Long Data 

The thread is retrieving long data in the result of executing a prepared statement. 

• Ping 

The thread is handling a server ping request. 

• Prepare 

The thread is preparing a prepared statement. 

• Processlist 

The thread is producing information about server threads. 

• Query 

Employed for user clients while executing queries by single-threaded replication applier threads, as well as by the replication coordinator thread. 

• Quit 

The thread is terminating. 

• Refresh 

