>>Ok, that makes sense.
>>
>>Under the following scenario:
>>
>>User 1 adds 4 detail lines
>>User 2 adds 3 detail lines
>>User 2 saves changes.
>>User 1 attempts to save but is not able to because header record has
>>been changed by user2 save.
>>
>>Since everything for user1 would rollback, they would have to reenter all detail lines
>>again. Is that correct?
>>
>>Thanks again.
>
>The detail lines would still be in the cursors/buffers. They could edit things and hit save button again.

Just wonder:-

let say total_qty = 20
if 10 computer at the same time hit save :
replace total_qty with total_qty - 1

some fail while some success, will total_qty still have the correct answer ?