> Which database have faster performance
> Firebird version 1.0.796 or Firebird version 1.5.4731 when installed
> in the same computer with the same configuration
>

1.5 contains optimisation enhancements that may help Firebird choose
better plans which would give better performance. If you have already
fiddled with the queries to make them optimum in 1.0, then 1.5 will
not help too much. Otherwise you will likely see a significant speed
increase in some cases. 1.5 will complain about ambiguous fields in
some cases, so you may need to check it still works properly with your
applications.

All else equal, FB 1.5 is faster and more stable than 1.0. See the 1.5
release notes for details on what has been fixed and enhanced. Same
for FB 2 is faster than FB 1.5 is a lot of cases, FB2 rejects even
more ambiguous queries. FB 2 contains some enhancements to indices
that really improve garbage collection when an index contains lots of
duplicates, which may be really noticable.

I suggest you use 1.5 to release on (at the moment, 2 is beta), and
begin making sure your application runs fine against FB 2 so you can
take advantage of it as soon as it is stable.

Adam