Horton

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  1. Using LIKE expression problem..

    Michael Ryan S. Puncia <mpuncia@census.gov.ph> — 2004-05-12T06:18:48Z

    Hi everybody..

    

     Before anything else I would like to thank all those person who answers
my previous question. again thank you very much

 

This is my question .

    

     In my query .. Select * from table1 where lastname LIKE  'PUNCIA%'..

 

In the query plan ..it uses seq scan rather than index scan .. why ? I have
index on lastname, firtname. 

 

 

Thanks

  2. Re: Using LIKE expression problem..

    Christopher Kings-Lynne <chriskl@familyhealth.com.au> — 2004-05-12T06:48:29Z

    > In the query plan ..it uses seq scan rather than index scan .. why ? I 
> have index on lastname, firtname…

Have you run VACUUM ANALYZE; on the table recently?

Chris

  3. Re: Using LIKE expression problem..

    Michael Ryan S. Puncia <mpuncia@census.gov.ph> — 2004-05-12T07:46:07Z

    Yes , I already do that but the same result .. LIKE uses seq scan

-----Original Message-----
From: pgsql-performance-owner@postgresql.org
[mailto:pgsql-performance-owner@postgresql.org] On Behalf Of Christopher
Kings-Lynne
Sent: Wednesday, May 12, 2004 2:48 PM
To: Michael Ryan S. Puncia
Cc: pgsql-performance@postgresql.org
Subject: Re: [PERFORM] Using LIKE expression problem..

> In the query plan ..it uses seq scan rather than index scan .. why ? I 
> have index on lastname, firtname.

Have you run VACUUM ANALYZE; on the table recently?

Chris


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  4. Re: Using LIKE expression problem..

    Christopher Kings-Lynne <chriskl@familyhealth.com.au> — 2004-05-12T07:59:10Z

    Are you in a non-C locale?

Chris

Michael Ryan S. Puncia wrote:

> Yes , I already do that but the same result .. LIKE uses seq scan
> 
> -----Original Message-----
> From: pgsql-performance-owner@postgresql.org
> [mailto:pgsql-performance-owner@postgresql.org] On Behalf Of Christopher
> Kings-Lynne
> Sent: Wednesday, May 12, 2004 2:48 PM
> To: Michael Ryan S. Puncia
> Cc: pgsql-performance@postgresql.org
> Subject: Re: [PERFORM] Using LIKE expression problem..
> 
> 
>>In the query plan ..it uses seq scan rather than index scan .. why ? I 
>>have index on lastname, firtname.
> 
> 
> Have you run VACUUM ANALYZE; on the table recently?
> 
> Chris
> 
> 
> ---------------------------(end of broadcast)---------------------------
> TIP 7: don't forget to increase your free space map settings
>

  5. Re: Using LIKE expression problem..

    Michael Ryan S. Puncia <mpuncia@census.gov.ph> — 2004-05-12T08:17:36Z

    Sorry .. I am a newbie and I don't know :( 
How can I know that I am in C locale ?
How can I change my database to use C locale?



-----Original Message-----
From: pgsql-performance-owner@postgresql.org
[mailto:pgsql-performance-owner@postgresql.org] On Behalf Of Christopher
Kings-Lynne
Sent: Wednesday, May 12, 2004 3:59 PM
To: Michael Ryan S. Puncia
Cc: pgsql-performance@postgresql.org
Subject: Re: [PERFORM] Using LIKE expression problem..

Are you in a non-C locale?

Chris

Michael Ryan S. Puncia wrote:

> Yes , I already do that but the same result .. LIKE uses seq scan
> 
> -----Original Message-----
> From: pgsql-performance-owner@postgresql.org
> [mailto:pgsql-performance-owner@postgresql.org] On Behalf Of Christopher
> Kings-Lynne
> Sent: Wednesday, May 12, 2004 2:48 PM
> To: Michael Ryan S. Puncia
> Cc: pgsql-performance@postgresql.org
> Subject: Re: [PERFORM] Using LIKE expression problem..
> 
> 
>>In the query plan ..it uses seq scan rather than index scan .. why ? I 
>>have index on lastname, firtname.
> 
> 
> Have you run VACUUM ANALYZE; on the table recently?
> 
> Chris
> 
> 
> ---------------------------(end of broadcast)---------------------------
> TIP 7: don't forget to increase your free space map settings
> 

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               http://www.postgresql.org/docs/faqs/FAQ.html

  6. Re: Using LIKE expression problem..

    Joseph Shraibman <jks@selectacast.net> — 2004-05-19T02:51:30Z

    Use the text_pattern_ops operator when creating the index, see:
http://www.postgresql.org/docs/7.4/static/indexes-opclass.html

Michael Ryan S. Puncia wrote:
> Sorry .. I am a newbie and I don't know :( 
> How can I know that I am in C locale ?
> How can I change my database to use C locale?
> 
> 
> 
> -----Original Message-----
> From: pgsql-performance-owner@postgresql.org
> [mailto:pgsql-performance-owner@postgresql.org] On Behalf Of Christopher
> Kings-Lynne
> Sent: Wednesday, May 12, 2004 3:59 PM
> To: Michael Ryan S. Puncia
> Cc: pgsql-performance@postgresql.org
> Subject: Re: [PERFORM] Using LIKE expression problem..
> 
> Are you in a non-C locale?
> 
> Chris
> 
> Michael Ryan S. Puncia wrote:
> 
> 
>>Yes , I already do that but the same result .. LIKE uses seq scan
>>
>>-----Original Message-----
>>From: pgsql-performance-owner@postgresql.org
>>[mailto:pgsql-performance-owner@postgresql.org] On Behalf Of Christopher
>>Kings-Lynne
>>Sent: Wednesday, May 12, 2004 2:48 PM
>>To: Michael Ryan S. Puncia
>>Cc: pgsql-performance@postgresql.org
>>Subject: Re: [PERFORM] Using LIKE expression problem..
>>
>>
>>
>>>In the query plan ..it uses seq scan rather than index scan .. why ? I 
>>>have index on lastname, firtname.
>>
>>
>>Have you run VACUUM ANALYZE; on the table recently?
>>
>>Chris
>>
>>
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>>TIP 7: don't forget to increase your free space map settings
>>
> 
> 
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> 
>                http://www.postgresql.org/docs/faqs/FAQ.html
> 
> 
> 
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