Re: C Language Stored Procedure Returning No Data

On Feb 2, 2006, at 7:17 PM, Michael Fuhr wrote:

> On Wed, Feb 01, 2006 at 12:56:30PM -0500, bfraci@aol.com wrote:
>> From a C stored procedure, how can I tell Postgres to pass on to
>> the Java client that there is No Data? A zero length byte array or
>> a null value is not the same as No Data.
>
> If you declare the function with "RETURNS bytea" then the function
> must return something; if zero-length data and NULL aren't suitable
> for indicating no data then you could raise an error and catch that
> error in the client.  Another possibility would be to make the
> function set-returning ("RETURNS SETOF bytea" and some code changes)
> and return no rows to indicate no data.


Another possibility is to log an exception with elog & company.
However that will also have the side effect of rolling back the txn
if you are currently in one.

--
Jeff Trout <jeff@jefftrout.com>
http://www.jefftrout.com/
http://www.stuarthamm.net/