Do you have the DBMS user guide from GE? The easiest way is to use
Guided SQL. In the From Tables, drop in something easy like
REG_B_PAT. In Select Columns, drop in PAT_NAME and MRN. Then in
Where columns meet these conditions:, drop in PAT_NAME='PATIENT,
TEST'. F10 and it will run. You'll get a list with the one patient
and their MRN.
Queries will get more complicated obviously, but thats the basics. A
lot of your success will depend on your knowledge of traditional SQL.