Re: query reboot pgsql 9.5.1 - Mailing list pgsql-general

On Fri, Mar 4, 2016 at 3:52 PM, Felipe de Jesús Molina Bravo <fjmolinabravo@gmail.com> wrote:

Now i execute the same in pgsql 9.4.5 and all is fine!!!

The EXPLAINs are:

- pgsql 9.5.1:

   Nested Loop Left Join  (cost=0.03..492944.81 rows=276095 width=4)
     ->  Seq Scan on _gc_tb a  (cost=0.00..3321.30 rows=120130 width=66)
       ->  Bitmap Heap Scan on _gc_cat b  (cost=0.03..4.06 rows=2 width=70)
             Recheck Cond: ((arama <@ a.arama) AND (a.arama <@ arama))
                 ->  Bitmap Index Scan on _gc_cat_arama_gin
                 (cost=0.00..0.03 rows=2 width=0)
                                Index Cond: ((arama <@ a.arama) AND
                                (a.arama <@ arama))


- pgsql 9.4.5:
   Nested Loop Left Join  (cost=0.03..492944.81 rows=276095 width=4)
     ->  Seq Scan on _gc_tb a  (cost=0.00..3321.30 rows=120130 width=66)
        ->  Bitmap Heap Scan on _gc_cat b  (cost=0.03..4.06 rows=2 width=70)
               Recheck Cond: ((arama <@ a.arama) AND (a.arama <@ arama))
                        ->  Bitmap Index Scan on _gc_cat_arama_gin
                        (cost=0.00..0.03 rows=2 width=0)
                                       Index Cond: ((arama <@ a.arama) AND
                                       (a.arama <@ arama))

The above are exactly the same, so if they are indeed from the different versions I do not see an issue. The question to ask here is whether the above are actually from the different Postgres instances?

yes these are differents 

So is each Postgres instance running in a separate container and if so are they set up the same?

Yes, is the same configuration!!

I suspect your 9.5.1 database has not been analyzed yet and therefore the statistics are off.

Do the following in the 9.5.1 database and then retry your query.

ANALYZE VERBOSE public._gc_cat;
ANALYZE VERBOSE public._gc_tb;

--

Melvin Davidson
I reserve the right to fantasize.  Whether or not you
wish to share my fantasy is entirely up to you.