Re: why does seq scan instead of index scan

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От 中川 誠貴
Тема Re: why does seq scan instead of index scan
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Msg-id 6A4B2F5F400049FEB3DF73B95BEA20EE@IVPNAKAGAWAPC
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Ответ на Re: why does seq scan instead of index scan  (Tom Lane <tgl@sss.pgh.pa.us>)
Ответы Re: why does seq scan instead of index scan  (Dmitriy Igrishin <dmitigr@gmail.com>)
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Thank you for your response.

Are there any technique to index that query for like search on Text[] 
Columns?


Thanks.


Nakagawa Maskai


--------------------------------------------------
From: "Tom Lane" <tgl@sss.pgh.pa.us>
Sent: Saturday, January 15, 2011 2:56 AM
To: "中川 誠貴" <nakagawa@ivp.co.jp>
Cc: <pgsql-sql@postgresql.org>
Subject: Re: [SQL] why does seq scan instead of index scan

> 中川 誠貴 <nakagawa@ivp.co.jp> writes:
>> I'm trying to use like 'xx%' search on Text[] column.
>> I thought it uses index scan. But actually it uses seq scan.
>
>> Why?
>
> Those ANY expressions are not indexable.
>
> regards, tom lane
>
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> Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org)
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