Row locking problem

I am testing an old Forms 3 program against DBMS 7.3.3.5. The Forms program is doing something I cannot explain and it is related to row locking.

I am using 30 terminals to run this test and all 30 users insert records at the same time through the Forms program. After this, the 30 users retrieve the same records for update at the same time. (At this point, Forms try to lock the records). When the commit key was pressed, 10 users went OK but the others got a message saying Forms failed to reserve the records.

I checked my code and test data. I am pretty sure that the users were accessing different records so that the lock should work for all of them.

I then thought this had to be something to do with the fact that the records were all created at the same time originally. So I did the test again and this time the users were retrieving records at random (I had a large volume of data which existed before the test). There was no locking problem!!

I am looking for an explanation of this behaviour. I think it is related to how Oracle performs row lock and there may be some limitations especially with records adjacent to each other. Any suggestions would be appreciated. Received on Mon Aug 23 1999 - 19:57:41 CDT