Message-ID: <422350F6.1050106@acm.org>
Date: Mon, 28 Feb 2005 09:12:22 -0800
From: TJ O'Donnell <tjo@acm.org>
Reply-To: tjo@acm.org
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To: Michael Fuhr <mike@fuhr.org>
Cc: pgsql-sql@postgresql.org
Subject: Re: SQL error: function round(double precision, integer) does
References: <4222570F.5080901@acm.org> <20050228163309.GA105@winnie.fuhr.org>
In-Reply-To: <20050228163309.GA105@winnie.fuhr.org>
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I got round(numeric,int) working OK, but it's got me thinking (a dangerous thing!).
Is there some fundamental reason for round(dp) but round(numeric,int)?
Shouldn't they be, at least, consistent, having round(numeric)
or round(dp,int)?
Am I missing something?

Thanks,
TJ

Michael Fuhr wrote:
> On Sun, Feb 27, 2005 at 03:26:07PM -0800, TJ O'Donnell wrote:
> 
> 
>>ERROR:  function round(double precision, integer) does not exist
> 
>                          ^^^^^^^^^^^^^^^^
> [snip]
> 
> 
>>The functions described at:
>>http://www.postgresql.org/docs/7.4/static/functions-math.html
>>show that round(numeric,int) should work ok.
> 
>                   ^^^^^^^
> 
> The two-argument form of round() expects the first argument to be
> numeric, not double precision.  There's no implicit cast from double
> precision to numeric, so you'll have to use an explicit cast:
> 
> SELECT ... round((expression)::numeric, 2) ...
>