From: Iain <iain@mst.co.jp>
To: email_daniel_h@yahoo.com.br
To: pgsql-sql@postgresql.org
Subject: Re: Simple SQL question
Date: Tue, 9 Mar 2004 14:37:30 +0900
Message-ID: <00d201c40598$9d96cc50$7201a8c0@mst1x5r347kymb> (raw)
References: <404C7EE3.8010006@yahoo.com.br>
<20040308184440.GG588@64.81.242.180>
<404D4667.10206@yahoo.com.br>
Sorry, did I write "ANALYSE SELECT .... "?
It's supposed to be "EXPLAIN [ANALYSE] [VERBOSE] SELECT ..."
----- Original Message -----
From: "Daniel Henrique Alves Lima" <email_daniel_h@yahoo.com.br>
To: <pgsql-sql@postgresql.org>
Sent: Tuesday, March 09, 2004 1:21 PM
Subject: Re: [SQL] Simple SQL question
> Thank you, Jeremy.
>
> I've built a function that returns a string from (cd_teacher, cd_course)
> and i've create a functional index over this function, like :
>
> create index teacher_course_idx on teacher_course
> (build_unique_2p(cd_teacher,cd_course));
> select * from teacher_course where build_unique_2p(cd_teacher,cd_course)
> in ('1:2','23:11','563','341');
>
> Is it possible to use "array cast" over cd_teacher and cd_course (just
> an idea, i don't known the sintaxe), like:
>
> select * from teachar_course where cast((cd_teacher,cd_course) as array)
> in ('{1,2}','{23,11}','{563,341}');
>
> ?
>
> I'm using postgreSQL 7.34
>
> Thanks !!!
>
> Jeremy Semeiks wrote:
>
> >You could use a subselect of unions:
> >
> >select * from teacher_course where (cd_course, cd_teacher) in
> >(select 1, 2 union select 23, 11 union select 563, 341)
> >
> >Maybe there's a more concise way, though.
> >
> >- Jeremy
> >
> >
> >
>
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 9: the planner will ignore your desire to choose an index scan if your
> joining column's datatypes do not match
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To: pgsql-sql@postgresql.org
Cc: iain@mst.co.jp, email_daniel_h@yahoo.com.br
Subject: Re: Simple SQL question
In-Reply-To: <00d201c40598$9d96cc50$7201a8c0@mst1x5r347kymb>
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