Re: index returns different output

What LOCALE setting do you run the postmaster in?

This looks like it might be the known problem with LIKE index
optimization not coping very well with non-ASCII collation orders.
(It tries, but if you have collation rules where multicharacter
patterns are treated specially, it tends to do the wrong thing...)

You can find lots of discussion about this in the pgsql mailing
list archives.  I don't think anyone's worked out a complete solution
short of not doing the optimization at all in non-ASCII locales :-(

			regards, tom lane