balasubramanian c r <crbs.sie...@gmail.com> writes:
> when Operator '@>' is used the index is used and the execution time is 60ms.
Yeah ... note that it's predicted to return just one row, and that
guess is correct:
> Bitmap Heap Scan on public.address18 (cost=261.25..262.52 rows=1 width=4)
> (actual time=58.992..58.994 rows=1 loops=1)
> when Operator '&&' is used the index is used and the execution time is 60ms.
> It is performing sequential scan which is not expected.
I do not see why you expect that. This case retrieves many more rows
than the other one, both in the planner's estimate and in reality:
> Seq Scan on public.address18 (cost=0.00..77215.11 rows=247741 width=4)
> (actual time=0.063..1880.467 rows=247741 loops=1)
An indexscan is not necessarily better than a seqscan for such cases...
> When i disable the sequential scan the execution time is increased
> significantly.
... so, indeed, the planner was correct to use a seqscan.
> Not expecting this behavior currently.
Your expectation is faulty.
regards, tom lane
