Re: Pgsql dynamic statements and null values

Ragnar Hafstað wrote:
> On Tue, 2005-03-08 at 16:30 -0600, Guy Rouillier wrote:
>> We use a dynamic statement in a pgsql stored function to insert rows
>> into a table determined at run time.  After much debugging, I've
>> discovered that a null incoming argument will cause the dynamic
>> statement to evaluate to null.  The error message emitted is "unable
>> to execute null statement."
>
> can't you use COALESCE() ?

Thanks Ragnar and Martijn for the replies.  NULLIF doesn't seem applicable here as I already have a null value coming
in,so I'm not comparing it to anything.  I had tried COALESCE before my original post and it produced the same result:
cannotexecute null statement.  However, your prompting motivated me to try a couple more alternatives.  Of the many I
tried,here is one that works: 

coalesce(quote_literal(inval), 'NULL')

Nice to know, but given the verbosity, I think I'll stick with my check_null(inval).  A worthwhile exercise, though,
sinceI can now reduce that function to this one line. 

--
Guy Rouillier