I have 2 data which are in .sas7bdat format and I need to perform a left join on them based on some condition. To give an overview of the PROC SQL it is as follows:

PROC SQL;
  CREATE TABLE XYZ 
     SELECT T1.A,
     case statement....,
     FROM T1 left join T2 ON
     T1.A= T2.A
     T1.B=T2.B AND
     UPCASE(T1.C)="class1"
    quit;

Both the SAS datasets are around 2GB each. Any efficient way I can get this done. The above statement takes almost an hour to complete and generate the output.
I am fine using data step operation as well if that will provide better performance than above.
I do not have memory limitation if that is a question:
RAM: 64 GB. Incase, this information is helpful.