Transaction locks
Understanding the sizes, durations, modes, and objects
of transaction locks can help you understand why processes encounter
suspension or timeout or deadlock, and how you might prevent that
contention.
Lock size
The size (sometimes scope or level ) of a lock on data in a table describes the amount of data that is controlled by the lock. The same piece of data can be controlled by locks of different sizes.
The duration of a lock
The duration of a lock is the length of time the lock is held. It varies according to when the lock is acquired and when it is released.
Lock modes and compatibility of locks
The mode of a lock tells what access to the locked object is permitted to the lock owner and to any concurrent processes.
How access paths affect locks
The access path that Db2 uses can affect the mode, size, and even the object of a lock.