I am looking for an example on how to use a hash and hash iterator to iterate through a data set inside a DS2 data program. As practical application I would like to build the Cartesian product of two tables. Each of the tables is a list of ID and Value and I want in face to end up with a data set containing all possible pairs of these 2 sets of Value. I tried something like below but is not working. It looks like rc=hi.first(); returns an error code rc=4 but I cannot find anywhere what that means. proc ds2; data one (overwrite=YES); method run();   set post.workPC (RENAME=(Value=Value1 TblID=TblID1)); end; enddata; run; data two (overwrite=YES); method run();   set post.workPC (RENAME=(Value=Value2 TblID=TblID2));   if TblID2 gt 1 then output; end; enddata; run; data prodcart (overwrite=Yes); declare double TblID2 rc; declare char(10) Value2; declare package hash h ('two'); declare package hiter hi('h'); method init();    rc = h.defineKey('TblID2');     rc = h.defineData('Value2');     rc = h.defineDone();   end; method run(); set one; rc=hi.first(); put TblID2 Value2 TblID1 Value1; end; run; quit; ... View more