How to execute Postgres Functions from Appian

Hi 

I Would like to know how we can execute Functions in Postgres from Appian. Can I achieve it by using Execute Stored Procedure Smart Service or a!executeStoredProcedureOnSave. 

If these doesn't work is there any smart service or function in Appian that I can use to achieve this functionality.

Help is Much Appreciated.

Thanks,

Srikanth