On 18 October 2012 17:44, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Thom Brown <thom(at)linux(dot)com> writes:
>> And as a side note, how come it's impossible to get the planner to use
>> an index-only scan to satisfy the query (disabling sequential and
>> regular index scans)?
>
> Implementation restriction - we don't yet have a way to match index-only
> scans to expressions.
Ah, I suspected it might be, but couldn't find notes on what scenarios
it's yet to be able to work in. Thanks.
--
Thom