From: Yeb Havinga <yebhavinga@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Mark Rostron <mrostron@ql2.com>
Cc: pgsql-admin@postgresql.org <pgsql-admin@postgresql.org>
Subject: Re: how do i query the type of an object?
Date: Thu, 12 Aug 2010 10:14:59 +0200
Message-ID: <4C63AD83.3060602@gmail.com> (raw)
In-Reply-To: <1823.1281577198@sss.pgh.pa.us>
References: <FD020D3E50E7FA479567872E5F5F31E30459E0E83C@ex01.corp.ql2.com>
<1823.1281577198@sss.pgh.pa.us>
Tom Lane wrote:
> Mark Rostron <mrostron@ql2.com> writes:
>
>> Is there some way to query the data-type of '<some value expression>'?
>>
>
> There's a SQL-standard construct called IS OF, and a function called
> pg_typeof, but it's not real clear whether either of those would help
> you.
>
I failed finding IS OF in the pg documentation, however,
http://farrago.sourceforge.net/design/UserDefinedTypesAndRoutines.html
had a reference to it.
postgres=# create table a(a) as select 1;
SELECT 1
postgres=# select * from a where a IS OF (integer);
a
---
1
(1 row)
While learning this somehow triggers the 'cool I just learned some new
obscure SQL trick' feeling, I am not sure if it is really useful without
CREATE TYPE foo UNDER bar.
regards,
Yeb Havinga
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To: pgsql-admin@postgresql.org
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Subject: Re: how do i query the type of an object?
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