Multiple placing of a lock.
A lock cumulation occurs when the name, argument, and lock mode of the elementary locks are all the same. The cumulation counter is increased by 1 after every subsequent cumulation, and is reduced by 1 every time a lock cumulation is released. The lock itself is released when the counter reaches 0.
There are the following types of locks:
Shared (read lock):Multiple transactions can hold a read lock simultaneously (for the purposes of reading data; that is, the data is not changed)
Exclusive (write lock):Simultaneous read or write locks on this object are rejected. Only the lock owner can place further locks. This is known as cumulation.
Exclusive but not cumulative lock:With this type of lock, even the original user can only place it once.
Optimistic lock:Behaves like a shared lock, but is converted into an exclusive lock when the data is actually changed.
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SAP przykład użycia LOCK-CUMULATION pomoc. Jak działa lock-cumulation kod programu ABAP. Wykorzystanie kodu Lock-Cumulation w programie funtion module SE37. Obsługa funkcji lock-cumulation
w klasie.
Słownik i definicje SAPa na L.