Proc Sql Join with Inequality Condition

[ChrisNZ]

@Astounding The BY statement really slows things down. But more so for SET it seems. Without BY, SET is faster.

I suppose it's to with managing the PDV: MERGE populates it once per key value for all tables, SET populates it once per key value per table, so the underlying table-reading routine must be different. But I am only making assumptions here.

The values are CPU-bound on my server: 

data BASE ;
  do I=1 to 1e8;
    output ;
  end;
run;

sasfile BASE load;

data _null_ ;set   BASE;       run; * 3.8s;
data _null_ ;merge BASE;       run; * 5.4s; 

data _null_ ;set   BASE; by I; run; * 9.5s;
data _null_ ;merge BASE; by I; run; * 9.3s; 

sasfile BASE close;