Re: exists

Stephan Szabo wrote:

>>Limit  (cost=48.39..48.39 rows=1 width=70)
>>   ->  Sort  (cost=48.39..48.39 rows=2 width=70)
>>         ->  Hash Join  (cost=18.46..48.38 rows=2 width=70)
>>               ->  Index Scan using u_p_key on u  (cost=0.00..27.66 rows=48 width=28)
>>               ->  Hash  (cost=18.39..18.39 rows=28 width=42)
>>                     ->  Seq Scan on d  (cost=0.00..18.39 rows=28 width=42)
>>               SubPlan
>>                 ->  Nested Loop  (cost=0.00..4.04 rows=1 width=20)
>>                       ->  Index Scan using a_pkey on a  (cost=0.00..2.01 rows=1 width=4)
>>                       ->  Index Scan using p_pkey on pu  (cost=0.00..2.02 rows=1 width=16)
>>                 ->  Index Scan using m_u_and_p_key on m  (cost=0.00..3035.22 rows=1363 
>>width=44)
>>
> 
> At least, what was the query that generated this and is it running
> slowly or otherwise giving problems?  The total explain doesn't seem
> unreasonable to my relatively untrained eyes in the absense of knowing the
> query :)
> 

Well the total cost should be at least as big as the sub-costs, no?  Doesn't that seem 
strange?


-- 
Joseph Shraibman
jks@selectacast.net
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