Re: exists

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От Joseph Shraibman
Тема Re: exists
Дата
Msg-id 3B82F9B1.6020401@selectacast.net
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Ответ на Re: exists  (Joseph Shraibman <jks@selectacast.net>)
Список pgsql-sql
I'm running 7.1.3.  What does 'rows=10000' mean?   The number of rows returned or the 
number postgres has to look through?

Tom Lane wrote:
> Joseph Shraibman <jks@selectacast.net> writes:
> 
>>Why does explain show more than one row, even if there is a LIMIT = 1?
>>
> 
> What version are you running?  I get results like
> 
> regression=# explain select * from tenk1 limit 1;
> NOTICE:  QUERY PLAN:
> 
> Limit  (cost=0.00..0.03 rows=1 width=148)
>   ->  Seq Scan on tenk1  (cost=0.00..333.00 rows=10000 width=148)
> 
> EXPLAIN
> 
> which seems at least moderately self-explanatory.
> 
>             regards, tom lane
> 


-- 
Joseph Shraibman
jks@selectacast.net
Increase signal to noise ratio.  http://www.targabot.com



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