I would consider using RPCFUNC on transaction object. Far less embedded SQL to write. You define the procedure as local external on transaction class. Then call it like any other function the transaction class. DBError fires if error occurs. - AND - you can still also check SQLCode etc.

Can you give me an example for achieving this? Do you mean to say that declare the procedure as local external function in n_tr? If that would be the case you will have to change the signature each time when you change the procedure signature (Input parameter). Correct?

That is very true! You may consider inserting a layer of inheritance between Transaction and your "n_tr_CurrentlyUsed". In that intermediate layer you could define all the local external functions as PRIVATE + add PUBLIC PowerScript functions. Each such "wrapper" function in PoewrScript pre/post-processes input/output data for that specific function. EX: A procedure having an OUTPUT string => Such poarameter requires allocating memory in PBVM up front.

This intermediate layer has one single purpose - provide easy access to each relevant user-defined functions and stored procedure. For each wrapper function you can design how you want to call it: External function; embedded SQL; DataWindow in DataStore; or some mixture.

Documentation > F1-Help > Search for "RPCFUNC"> Select topic titled "Using Transaction objects to call stored procedures".

That page introduces you to RPCFUNC and contains a 5-step how-to guide.