Re: Postgres mystery

Michael Fuhr wrote:

>On Wed, Mar 30, 2005 at 09:11:09AM +0200, Shaun Clements wrote:
>
>
>>Can anyone tell me what the problem is here:
>>I am inserting into a table via a stored procedure, to a few columns within
>>the table and postgres is throwing a
>>CANNOT EXECUTE NULL QUERY.
>>
>>EXECUTE ''INSERT INTO table (column1, column2, column3,
>>''||quote_ident(column4)||'') values
>>(''||quote_literal(RECORDNAME.column1)||'',''||quote_literal(RECORDNAME.colu
>>mn2)||'',''''stringvalue'''',''||quote_literal(RECORDNAME.column2)||'')'';
>>
>>
>
>One of the operands to || is probably NULL, so the entire INSERT
>string ends up being NULL.  Example:
>
>SELECT 'abc' || 'def';
> ?column?
>----------
> abcdef
>(1 row)
>
>SELECT 'abc' || NULL;
> ?column?
>----------
>
>(1 row)
>
>Looks like you need to check for NULL or use COALESCE to convert
>NULL to something else.
>
>
>
That something else you ought to do appears in the documentation User
Comments at

http://www.postgresql.org/docs/8.0/interactive/functions-conditional.html