Perhaps a MUTEX might be of use.. so that only one process is performing a SELECT at a time?

Once you have the object you can DELETE at leisure, so wrapping a MUTEX around the SELECT would ensure the safety you're looking for (look around for documentation on inter-process communications, or the chapter in the Camel book).

Update: I'm being downvoted on this one.. it seems my experience in multitasking embedded and workstation environments is causing consternation for the readers of this thread...

Update 2: As Foxcub correctly points out below, it is futile to protect the SELECT using a MUTEX but not wrapping the DELETE in the same call. Thus I am completely wrong, my logic is entirely flawed. Apologies.

Update 3: Added readmore tags.

In reply to Re: Database queue logic by monarch
in thread Database queue logic by Marcello

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