This join will be detected by the SQL Procedure and passed by the SAS/ACCESS engine directly to the DBMS server. The resulting rows will be passed back to the SAS System. proc sql; select tab1.deptno, ...

you can use the SAS data set option RENAME= to rename that column for the duration of the query. You can also surround CASE in double quotes ("CASE") and set the PROC SQL option DQUOTE=ANSI. The ...