Hello Dmitry,

...

> In all IB/FB versions, it's possible to execute apriori singleton
> statements (EXECUTE PROCEDURE, INSERT RETURNING) with either
> isc_dsql_execute() or isc_dsql_execute2(out_sqlda=NULL), i.e. without
> returning the output values in the same round-trip.
>
> I'm trying to understand how this behavior should be formally treated:
>
> 1) as correct and results should be discarded after execution
> 2) as wrong and error should be thrown (no room to store output values)
> 3) as an incomplete operation waiting for isc_dsql_fetch() to get the
> results

...

As long as the statements with RETURNING continue to be described as stmt_exec_procedure, then I think solution 2) is the best option.

Best regards,
—
Olivier Mascia