Answer: A long Transaction Running Time means the connection hasn't performed a COMMIT or ROLLBACK for a long time since starting the current database transaction.

Note that each connection can only have one database transaction in progress at any given point in time; there is no such thing as "nested transactions", and if an application wants to run two different database transactions at the same time it must use two different database connections.

If the Locks Held number is larger than zero, it means other connections may be prevented from updating (and possibly even reading) rows this connection has locked; if that actually happens, this connection's Conn # will show up in the Blocked by Conn # for the other connections.

If the Uncommitted number is larger than Locks Held, it may be that this connection is repeatedly updating the same rows without committing the changes.