From: 中川 誠貴 <nakagawa@ivp.co.jp>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-sql@postgresql.org
Subject: Re: why does seq scan instead of index scan
Date: Sat, 15 Jan 2011 14:19:34 +0900
Message-ID: <6A4B2F5F400049FEB3DF73B95BEA20EE@IVPNAKAGAWAPC> (raw)
In-Reply-To: <8294.1295027762@sss.pgh.pa.us>
References: <49A94E2FF0F642B4ACBE09DB20CA5630@IVPNAKAGAWAPC>
<8294.1295027762@sss.pgh.pa.us>
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
> =?iso-2022-jp?B?GyRCQ2ZAbiEhQD81LhsoQg==?= <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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Subject: Re: why does seq scan instead of index scan
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