This may have been answered adequately already but I didn't see any closure...    The most direct answer to your question is that you forgot the where clause after the join.      proc sql;     create table DQ As       select              case                 when r.CostCentre ^= d.CostCentredq then 1               else 0             end as WrongCostCentre       from data.resources r,  valibla.dq_res d       where r.apples=d.apples AND r.oranges=d.oranges; quit;     If you really just want the rows where WrongCostCentre  =1 then add to the where clause, or add the having clause:   proc sql;     create table DQ As       select              case                 when r.CostCentre ^= d.CostCentredq then 1               else 0             end as WrongCostCentre       from data.resources r,  valibla.dq_res d       where r.apples=d.apples AND r.oranges=d.oranges       having WrongCostCentre=1;  /* Some would consider this an abuse of the having clause */   quit;     Of course, if you only want WrongCostCentre=1 rows, you don't need the CASE statement in the query. It would just be another condition in the where clause.    ... View more