I know this had been discussed numerous times and I'm beating a dead horse, but I'm wondering the following.

Say, after I create a table, I do the following:

alter table name add unique(num, date, line_no);

and then

alter table name add index (num)


Am I indexing num twice since it's the leftmost part of the unique? Or is unique just force MySQL to make that tuple unique and not index it?

Thanks for any and all feedback!

Don't know about MySQL, but in oracle and mssql, you would indeed be indexing your column NUM twice.

Curious about MySQL though...

CVM.