Re: Conditional Adding to a Table

You could use a LOCK TABLE statement to gain an exclusive lock, but a better approach is probably to put a unique constraint on whatever your check is and then just attempt the INSERT.

Hope this helps a little....

Allan.

Glenn Sullivan wrote:

> Greetings,
>
> I need to check a table to see if an item already exist in the table.
> It if does not, then I want to add it. Unfortunately, multiple processes
> (Solaris system) can be running at the same time. Sometimes, one process
> checks to see if an item exist and it does not. At the same time another
> process checks to see if the same item exist and it does not. Then both,
> add the item to the table. This is, of course, not what I want.
>
> I cannot seem to figure out how to do a conditional test to do something
> like this. If I could, then the whole operation could fit in one transaction
> with locking.
>
> Any ideas?
>
> Thanks,
> Glenn
>
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