"Joshua D. Drake" <jd(at)commandprompt(dot)com> writes:
>> The cost of preventing every stupid database use is too high.
> Although a notice that says:
> NOTICE: CREATE DUPLICATE INDEX y on test (col1);
> Probably isn't out of order.
You're omitting the (probably) several pages of C code that would be
needed to detect whether the index is really a duplicate or not.
regards, tom lane