> If I had set the primary key to (diag_id, create_time) would simple
> queries on
> diag_id still work well i.e.
> select * from tdiag where diag_id = 1234;
Yes. IIRC the performance penalty for using non-leading column of an index
is negligible. But why don't you try that on your own - just run an
explain and you'll get an immediate answer if that works.
regards
Tomas
