Is it possible to concatenate two values inside Proc SQL?

[DmytroYermak]

I have the following Proc SQL:

proc sql;
	create table dm1 as
	select STUDYID, DOMAIN, dm.SubjectID, USUBJID 
	from train.dm,train.cp
	where dm.subjectid=cp.subjectid 
	order by subjectid
;
quit;

 USUBJID should be the a concatination of SubjectID and  STUDYID: USUBJID = STUDYID || SubjectID . How can it be actualized inside the Proc SQL? Thank you!

[novinosrin · Accepted solution]

proc sql;
	create table dm1 as
	select STUDYID, DOMAIN, dm.SubjectID, SubjectID||STUDYID as USUBJID 
	from train.dm,train.cp
	where dm.subjectid=cp.subjectid 
	order by subjectid
;
quit; 

[DmytroYermak]

Thank you, novinosrin. I asked but even not having checked on my own).

[ballardw]

If any of your your SubjectID are shorter than the defined length of the variable you may get unwanted spaces in the middle of the USUBJID variable:

data junk;
   length subjectid $ 10;
   subjectid = 'abc';
   studyid = '123';
run;

proc sql;
   select studyid, subjectid,SubjectID||STUDYID as USUBJID 
   from junk;
run; 

If you don't want the space in the middle then use Cats(SubjectId,StudyId) as Usubjid

[Reeza]

CATS/CATT functions can be used similarly to any other function within PROC SQL.