"Donald Fraser" <demolish(at)cwgsy(dot)net> writes:
> Not sure whether you classify this as a bug or not?
It's a bug --- it's fixed for 7.4. 7.3 has some problems with the
timing of constant simplification in queries vs. predicate expressions.
I'm surprised you can get it to use the index at all, though, since the
system is going to think a condition involving <> is quite unselective.
regards, tom lane