Automatic Acquisition of Locks (Cont.) write(D)is processed as: if T;has a lock-X on D then write(D) else begin if necessary wait until no other trans.has any lock on D, if T;has a lock-S on D then upgrade lock on D to lock-X else grant T;a lock-X on D write(D) end; All locks are released after commit or abort Database System Concepts-5th Edition,Oct 5,2006 16.13 @Silberschatz,Korth and SudarshanDatabase System Concepts - 5 16.13 ©Silberschatz, Korth and Sudarshan th Edition, Oct 5, 2006 Automatic Acquisition of Locks (Cont.) write(D) is processed as: if Ti has a lock-X on D then write(D) else begin if necessary wait until no other trans. has any lock on D, if Ti has a lock-S on D then upgrade lock on D to lock-X else grant Ti a lock-X on D write(D) end; All locks are released after commit or abort