To do this, you'll have to have a few SQL commands run for every insert. First, the command needs to check to see if there is an ID greater than 1000. If there is , then you'll need to DELETE the first ID number, re-start the ID number sequence, and then INSERT the new data. If it's less than 1000, just INSERT it in.

Getting back that ID number can be problematic. It's do-able in MYSQL and Access that I know of, I'd wager PostgreSQL has a LastAutonumberEntered or the like somewhere in the docs. If not, try timestamping, and then searching for that timestamp (records entered less than, say, 1 minute ago) or searching on a different possibly unique field. I'd recommend wrapping all this in a transaction, for obvious reasons.

----Asim, known to some as Woodrow.


In reply to Re: Cycle through primary key with DBI by Asim
in thread Cycle through primary key with DBI by lestrrat

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