The SQL language is so robust, there's often more than one way to accomplish a task. In this Gist, I demonstrate how to extract the job user name from a qualified job name.

Extracting data from a string.sql

--
-- Author: Scott Forstie
-- Date  : July 14, 2020
--
--
-- Question: How do I extract the Job User Name from a qualfied job name?
-- Answer  : Use Locate_In_String with Substring
-- Bonus   : Did you know that the QSYS2.JOB_NAME built-in global variable gives you the qualfied job-name of the current connection?

values qsys2.job_name,
      substr(qsys2.job_name, 
             locate_in_string(qsys2.job_name, '/', 1, 1) + 1, 
             locate_in_string(qsys2.job_name, '/', 1, 2) -
             (locate_in_string(qsys2.job_name, '/', 1, 1)+1));