Re: [PERFORM] why my query is not using index??

[Francisco Reyes]

On Mon, 11 Oct 2004, John Meinel wrote:

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Postgres believes that it will cost 382 to do a sequential scan, versus 490 
for an indexed scan. Hence why it prefers to do the sequential scan. Try 
running explain analyze to see if how accurate it is.
With explain analyze I have with sequential scan on
Sort  (cost=382.01..382.15 rows=56 width=196)
(actual time=64.346..64.469 rows=24 loops=1)
And with seqscan off
Sort  (cost=490.82..490.96 rows=56 width=196)
(actual time=56.668..56.789 rows=24 loops=1)
So I guess that for this particular query I am better off setting the 
seqscan off.

---------------------------(end of broadcast)---------------------------
TIP 9: the planner will ignore your desire to choose an index scan if your
     joining column's datatypes do not match