>> The problem for me is, the Recheck Cond is then on the xpath() function
>> used by the function-based index. My understanding is that then the
>> database must actually call the xpath() function again on all matches
>> from
>> the index lookup.
>
> This is mistaken. It only happens if there are so many hits that the
> bitmap becomes lossy (which you can control to some extent anyway by
> adjusting work_mem).
Ah, great. Thanks for clarifying.
-- m@
