Re: Problems with order by, limit, and indices

Hi,

another interesting thing...
This is current 7.1.

slygreetings=> explain select * from users where variant_id=5 AND active='f'
order by rcptdate,variant_id,active limit 60;
NOTICE: QUERY PLAN:

Limit (cost=13005.10..13005.10 rows=60 width=145)
-> Sort (cost=13005.10..13005.10 rows=3445 width=145)
-> Index Scan using users_rcptdate_vid_key on users
(cost=0.00..12658.35 rows=3445 width=145)

EXPLAIN
slygreetings=> set enable_sort to off;
SET VARIABLE
slygreetings=> explain select * from users where variant_id=5 AND active='f'
order by rcptdate,variant_id,active limit 60;
NOTICE: QUERY PLAN:

Limit (cost=100013005.10..100013005.10 rows=60 width=145)
-> Sort (cost=100013005.10..100013005.10 rows=3445 width=145)
-> Index Scan using users_rcptdate_vid_key on users
(cost=0.00..12658.35 rows=3445 width=145)

EXPLAIN

Cost is something really wierd.... Why?

--
Sincerely Yours,
Denis Perchine

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