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Message-ID: <162867790901052230l25b10f08qa35f56856b9cc4c6@mail.gmail.com>
Date: Tue, 6 Jan 2009 07:30:53 +0100
From: "Pavel Stehule" <pavel.stehule@gmail.com>
To: "Gurjeet Singh" <singh.gurjeet@gmail.com>
Subject: Re: [HACKERS] ERROR: failed to find conversion function from
	"unknown" to text
Cc: "PGSQL General" <pgsql-general@postgresql.org>,
	"PGSQL Hackers" <pgsql-hackers@postgresql.org>
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Hello

2009/1/6 Gurjeet Singh <singh.gurjeet@gmail.com>:
> Q1: select '' union all select ''
> Q2: select '' union all select * from (select '' ) as s
>
> version: PostgreSQL 8.3.1, compiled by Visual C++ build 1400
>
> Hi All,
>
>     Q1 works just fine, but Q2 fails with:
>
> ERROR:  failed to find conversion function from "unknown" to text
>
>     Q2 is a generalization of a huge query we are facing, which we cannot
> modify. I don't think this is a 'removed-casts' problem generally faced in
> 8.3, but I may be wrong. Will adding some cast resolve this?

yes

postgres=#  select '' union all select * from (select ''::text ) as s;
 ?column?
----------


(2 rows)

regards
Pavel Stehule

>
> Best regards,
> --
> gurjeet[.singh]@EnterpriseDB.com
> singh.gurjeet@{ gmail | hotmail | indiatimes | yahoo }.com
>
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>
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