Re: significant slow down with various LIMIT

> Try this:
>
> ALTER TABLE ALTER plugins_guide_address
>   ALTER COLUMN city_id SET STATISTICS 1000;
> ANALYZE plugins_guide_address;
>
> Then try your query.
No luck... The same query time...

> I have one more diagnostic query to test, if the above doesn't work:
>
> explain analyze
> SELECT id FROM
>   (
>     SELECT core_object.id
>       FROM "core_object"
>       JOIN "plugins_plugin_addr"
>         ON ("core_object"."id" = "plugins_plugin_addr"."oid_id")
>       JOIN "plugins_guide_address"
>         ON ("plugins_plugin_addr"."address_id" =
>             "plugins_guide_address"."id")
>       WHERE "plugins_guide_address"."city_id" = 4535
>   ) x
>   ORDER BY id DESC
>   LIMIT 4;

Limit (cost=0.00..8.29 rows=4 width=4) (actual time=0.284..1322.792
rows=4 loops=1)
-> Merge Join (cost=0.00..993770.68 rows=479473 width=4) (actual
time=0.281..1322.787 rows=4 loops=1)
Merge Cond: (plugins_plugin_addr.oid_id = core_object.id)
-> Nested Loop (cost=0.00..887841.46 rows=479473 width=4)
(actual time=0.194..1201.318 rows=4 loops=1)
-> Index Scan Backward using
plugins_plugin_addr_oid_id on plugins_plugin_addr
(cost=0.00..51546.26 rows=1980627 width=8) (actual time=0.117..87.035
rows=359525 loops=1)
-> Index Scan using plugins_guide_address_pkey on
plugins_guide_address (cost=0.00..0.41 rows=1 width=4) (actual
time=0.003..0.003 rows=0 loops=359525)
Index Cond: (plugins_guide_address.id =
plugins_plugin_addr.address_id)
Filter: (plugins_guide_address.city_id = 4535)
-> Index Scan Backward using core_object_pkey on
core_object (cost=0.00..91309.16 rows=3450658 width=4) (actual
time=0.079..73.071 rows=359525 loops=1)
Total runtime: 1323.065 ms
(10 rows)