>>>>> "MichaelDBA" == MichaelDBA  <michael...@sqlexec.com> writes:

 MichaelDBA> Nope, vacuumed it and still got the bitmap index scans.

Let's see your explains. Here's mine:

# set enable_seqscan=false;  -- because I only have a few rows
SET
# insert into friend values (1,2),(2,5);
INSERT 0 2
# vacuum analyze friend;
VACUUM
# explain analyze SELECT user1_id FROM friend WHERE user2_id=2 UNION ALL select 
user2_id FROM friend WHERE user1_id=2;
                                                                   QUERY PLAN   
                                                                
------------------------------------------------------------------------------------------------------------------------------------------------
 Append  (cost=0.13..8.32 rows=2 width=4) (actual time=0.009..0.014 rows=2 
loops=1)
   ->  Index Only Scan using friend_user2_id_user1_id_idx on friend  
(cost=0.13..4.15 rows=1 width=4) (actual time=0.009..0.009 rows=1 loops=1)
         Index Cond: (user2_id = 2)
         Heap Fetches: 0
   ->  Index Only Scan using friend_pkey on friend friend_1  (cost=0.13..4.15 
rows=1 width=4) (actual time=0.003..0.004 rows=1 loops=1)
         Index Cond: (user1_id = 2)
         Heap Fetches: 0
 Planning Time: 0.271 ms
 Execution Time: 0.045 ms
(9 rows)

Note that you have to put some actual rows in the table; if it is
completely empty, you'll not get a representative result.

-- 
Andrew (irc:RhodiumToad)


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