On 11 October 2011 21:45, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Thom Brown <thom@linux.com> writes:
>> So an index-only scan is 30 times slower in this particular test case.
>
> Don't see why you'd find that unexpected. If you have to visit all the
> rows, a seqscan is usually going to be the best way. An indexscan only
> has a chance of winning when the index is much smaller than the table,
> which isn't the case in your example, even if you hadn't seen to it that
> the index wasn't particularly nicely physically ordered.
Ah okay, understood.
--
Thom Brown
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