Message-ID: <42231EB6.9F6D20F3@rodos.fzk.de>
Date: Mon, 28 Feb 2005 14:37:58 +0100
From: Christoph Haller <ch@rodos.fzk.de>
MIME-Version: 1.0
To: tjo@acm.org
Cc: pgsql-sql@postgresql.org
Subject: Re: SQL error: function round(double precision, integer) does not 
References: <4222570F.5080901@acm.org>
Content-Type: text/plain; charset=iso-8859-2
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TJ O'Donnell wrote:
> 
> I received the following error when executing a SQL statement:
> 
> SQL error:
> ERROR:  function round(double precision, integer) does not exist
> 
> In statement:
> 
> select id,smiles,smarts,parameter,oe_count_matches(smiles,smarts) as count,
>   round((parameter*oe_count_matches(smiles,smarts)),2) as psa,tpsa(smiles) as ctpsa,tpsa
>   from structure,tpsa
>   where id < 237610
>   and oe_count_matches(smiles,smarts) > 0
> 
> order by id;
> 
> The functions described at:
> http://www.postgresql.org/docs/7.4/static/functions-math.html
> show that round(numeric,int) should work ok.
> If I use round() without a second argument, it works OK, but
> this gives a loss of precision which I do not want.
> 
> Can anyone help me with this?
> 
> Thanks,
> TJ
> 

And round(numeric,int) does work ok. 
The error message is telling you 
there is double precision argument where a numeric 
is expected. 
And with 7.4.5 it says in addition 
HINT:  No function matches the given name and argument types. 
You may need to add explicit type casts.

Try 
round((parameter*oe_count_matches(smiles,smarts))::numeric,2) 

Works for me with double precision arguments. 

Regards, Christoph