For example, think of a user table... The user id is going to be unique. It would be a bad idea to use it as a foreign key in link tables, but it would be unique all the same

Quite true, but that is what I mean about "another uniqueness constraint". Personally, I usually call this "user_name" and have "user_id" be a auto increment primary key :).

The only reason I keep pushing this idea is that I have been bitten by it in the past. And in a OO-relational mapping class as well (although it was a custom class, and not a full system like yours). In the end I wrote a DBI wrapper which handled the differences between MySQL's 'last_insert_id' and PostgreSQL's 'pg_oid_status' which gave me a basic level of DBD agnosticism (well at least the DBD's I cared about that is).

Anyway, I'm not sure what I'm arguing anymore... I didn't get enough sleep last night and am not entirely coherent. :-)

Two words: Mountain Dew :)

-stvn

In reply to Re^5: Auto-Increment and DBD Agnosticism by stvn
in thread Auto-Increment and DBD Agnosticism by skyknight

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