> -----Original Message-----
> "Actually, I can't. Do you mean that index_name is a separate column or
> just an alias for index_col_name? The manual does have a line for the
> of UNIQUE but it never explains it!"
> Well all it means is that you can specify a name for the index. It's
> optional because in itself it doesn't do anything. Really it's for your
> convenience as much as anything.
> "Also, optional doesn't necessarily mean implied. In fact, are you sure
> that UNIQUE implies INDEX?"
> Yes, a unique one. To perhaps confuse things, so does KEY (KEY is a
> synonym for INDEX).
> Hmm, I'm not convinced. I'd think the opposite would be preferable in
>order to allow a column to be defined as UNIQUE without it being an INDEX.
>Then again, you might be right but not because of what can be found in the
To ensure that column values are UNIQUE would be horribly inefficient
if the column were not indexed. You'd have to do a full table scan
every time you added or modified a column value.
I'm beginning to wonder if you're trolling. Are you?
Paul DuBois, paul@stripped