Re: Many to many join seems slow?

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Drew Wilson
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Re: Many to many join seems slow?
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в 13:44:11
Msg-id
694A96DF-65A7-4DCD-972F-97081A554E1B@gmail.com
Ответ на
Re: Many to many join seems slow? (Daniel Cristian Cruz)
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Many to many join seems slow? Drew Wilson <drewmwilson@gmail.com>
Re: Many to many join seems slow? Alvaro Herrera <alvherre@commandprompt.com>
Re: Many to many join seems slow? Drew Wilson <drewmwilson@gmail.com>
Re: Many to many join seems slow? Heikki Linnakangas <heikki@enterprisedb.com>
Re: Many to many join seems slow? Drew Wilson <drewmwilson@gmail.com>
Re: Many to many join seems slow? "Daniel Cristian Cruz" <danielcristian@gmail.com>
Re: Many to many join seems slow? Drew Wilson <drewmwilson@gmail.com>
Yes, I'll be filtering by string value. However, I just wanted to see  
how long it takes to scan all translations in a particular language.

Drew

On May 15, 2007, at 9:00 AM, Daniel Cristian Cruz wrote:

> 2007/5/15, Drew Wilson :
>> =# explain SELECT s.source_id, s.value AS sourceValue, t.value AS
>> translationValue
>>        FROM
>>            source s,
>>            translation_pair tp,
>>            translation t,
>>            language l
>>        WHERE
>>            s.source_id = tp.source_id
>>            AND tp.translation_id = t.translation_id
>>            AND t.language_id = l.language_id
>>            AND l.name = 'French' ;
>>
>>                                                           QUERY PLAN
>> --------------------------------------------------------------------- 
>> ---
>> -----------------------------------------------------
>> Merge Join  (cost=524224.49..732216.29 rows=92447 width=97)
>
> This way you get all word matches for the French language. Shouldn't
> it be all matches for a specific word (s.value = 'word' in WHERE)?
>
> -- 
> Daniel Cristian Cruz

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