Difference between SAP locks and Database locks

[Former Member]

Hi all,

Can any body explain me what is technical difference b/n SAP locks that are shown in SM12 and Oracle Locks which are shown in DB01.

Thanks in advance.

Raja

[WolfgangJanzen]

Well, you need "logical locks" (those you see in SM12) if you want to create a new object (that might first exist only in the memory) and want to make sure that simultaneous operations will not create the same object. Well, you can compare that with semaphores.

Database locks are created automatically (by the DBMS) when you perform a modifying DB operation (UPDATE, DELETE, ...). Database locks are release when performing a database commit. Notice: ABAP systems will submit database commits in certain situations (e.g. when performing a roll-out after submitting synchronous RFC calls, when waiting for user input, etc.).

More information: search for keyword "LUW" (Logical Unit of Work), e.g. in the ABAP online help.

Regards, Wolfgang

[Former Member]

Hi,

SM12 locks

http://help.sap.com/saphelp_47x200/helpdata/en/37/a2e3ae344411d3acb00000e83539c3/frameset.htm

DB01 locks

http://help.sap.com/saphelp_47x200/helpdata/en/c2/2d7037ecc92a7ee10000009b38f8cf/frameset.htm

Hope this helps

Cheers

Soma

[Former Member]

Raja-

Just completed an interesting project identifying and deleting Oracle Lock Jams and having the ability to kill the process that causes them. Let me know if you still need help with this topic.