Orange_Crush
Resident windbag genius
- Joined
- Dec 1, 2004
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It's one of those things you don't pay attention to. I'm was pretty sure the tear off tab at the top had a number - now I'm questioning that. I spent a few years managing and analyzing big databases and got pretty good at SQL. If you want to make a database impervious to duplicate entries, you just use an ID number. ID and a matching name can exist elsewhere, but the main (or more public) database would only have an anonymous identifier. It's easy enough then to query the database and look for duplicates, records with no ID, or an ID out of range. Presumably a scanner would read the coded ID and enter it with the marked boxes.
Yep. That's what the primary key is for.