Re: Simple Query not using Primary Key Index

After resetting all statistics it still opts for a Seq Scan. I went ahead
to test with creating another table and querying that, and it shows on that
test table to be using the index. So I wonder if there is anything else
that may effect the planner. is there a way I can dog into this and see the
steps the planner performs while deciding which ap to use?

Thanks!

On Mon, Feb 6, 2017, 6:33 PM Vitaly Burovoy <vitaly(dot)burovoy(at)gmail(dot)com>
wrote:

> On 2/6/17, Podrigal, Aron <aronp(at)guaranteedplus(dot)com> wrote:
> > Hi,
> >
> > I noticed when I do a simple SELECT id FROM mytable WHERE id =
> > 'cb81d070-4213-465f-b32e-b8db43b83a25'::UUID Postgres does not use the
> > primary key index and opts for a Seq Scan.
> >
> > I of course did VACUUM ANALYZE and I have reset statistics But no sign.
> Is
> > there any particular thing I should be looking at?
>
> Postgres uses specified access methods according to table's statistics.
> If you have a small table, it is likely that Postgres uses SeqScan
> because it is similar or cheaper than IndexScan. That's why it can
> ignore existing indexes.
>
> --
> Best regards,
> Vitaly Burovoy
>