From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alan Gutierrez <alangutierrez@hotmail.com>
Cc: Bill <bchie@opensys.com.hk>
Cc: pgsql-sql@postgresql.org
Subject: Re: Re: DateDiff, IsNull?
Date: Tue, 14 Aug 2001 10:49:26 -0400
Message-ID: <17556.997800566@sss.pgh.pa.us> (raw)
In-Reply-To: <Pine.WNT.4.33.0108140634400.1680-100000@CX1198465-B>
References: <9lb25o$psq$1@news.tht.net>
<Pine.WNT.4.33.0108140634400.1680-100000@CX1198465-B>
Alan Gutierrez <alangutierrez@hotmail.com> writes:
> On Tue, 14 Aug 2001, Bill wrote:
>> And is it possible to override the existing function and
>> operator like "+" to become a concate?
> Overloading operators? *Please* tell me that this is impossible.
I've got bad news ;-) ... it's pretty easy.
regression=# select 'aa'::text + 'bb'::text;
ERROR: Unable to identify an operator '+' for types 'text' and 'text'
You will have to retype this query using an explicit cast
regression=# create operator + (procedure = textcat,
regression(# leftarg = text, rightarg = text);
CREATE
regression=# select 'aa'::text + 'bb'::text;
?column?
----------
aabb
(1 row)
Whether this is a good idea is another question --- but if Bill's
intent on not using the SQL-standard text concatenation operator "||",
he can do so.
regards, tom lane
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To: pgsql-sql@postgresql.org
Cc: tgl@sss.pgh.pa.us, alangutierrez@hotmail.com, bchie@opensys.com.hk
Subject: Re: Re: DateDiff, IsNull?
In-Reply-To: <17556.997800566@sss.pgh.pa.us>
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