--- In firebird-support@yahoogroups.com, "jasajona" <jasajona@...> wrote:

>
> Hello,
>
> Unique constraint creates unique index, but it is possible to achieve
> the same creating manually unique index. What is the difference
> between unique index and unique constraint?
>
> Thank You!

Don't bother defining a unique index. I don't know the history behind
it, but it smells like a work around ;)

If your data must be unique, declare a unique constraint.

Adam