some genral question about MAXDB

[nomadd_law]

hello guys i have some genral questions about maxdb regarding Locking Process

| BKPF | BERD00145761A B4C | tab_exclusive | BERD00145761..17FC | x'FFFE0000001

264FD' | row_exclusive |

In the example, the transaction running in the process with PID 0xB4C (=2892 in the

Windows Task Manager) holds an exclusive table lock on table BKPF, while

another transaction (PID 0x17FC) tries to lock a row of the same table exclusively. This transaction

has to wait until process PID 0xB4C performs a COMMIT or ROLLBACK.

What does they mean with performs a COMMIT or ROLLBACK ?

[Former Member]

Hi,

please use Expert Session about MaxDb locking mechanism additionally to Burkhard's answer.

Expert Session

Session 12: Analysis of SQL Locking Situations

link for download of the recording and slides -> http://maxdb.sap.com/training/

Please use parameter MaxSQLLOCKs to avoid table Locks. In the session you will get information when a so called lock escalation ( transfer row locks into table lock) is executed. Exclusive table locks should be avoided because then other users cannot access the table anymore.

Regards, Christiane

[Former Member]

Hello,

a COMMIT finalizes the sequence of the commands which has made changes (INSERT/UPDATE/DELETE) and made them visible to other users.

A ROLLBACK undoes all changes you have made. Other users will never seen this changes.

During change operations of one user session the database sets locks to prevent that other users made changes on the same data row until the lock holder has finalized the changes.

Regards,

B*