I forgot the semicolon and the quit;

proc sql; create table newdataset as select a.* from currentmonth a, standard b where a.market=b.market and a.product=b.product ; quit;

This is equivalent to proc sql; create table newdataset as select a.* from currentmonth a inner join standard b on a.market=b.market and a.product=b.product ; quit;

If you want all lines of currentmonth in newdataset no matter if the same line was found in standard use a left join: proc sql; create table newdataset as select a.* from currentmonth a left join standard b on a.market=b.market and a.product=b.product ; quit;

This may be useful if the market is spelled differently in standard than in the dataset of your company as you wrote.

I do not know much about string matching. Just one thing substr("Hello",2,2) returns "el". You might want to try to match only the first few characters of the market: and substr(a.product,1,5)=substr(b.product,1,5).

There are may string manipulation functions. If you specify your difficulty in matching lines, someone might be able to give more useful advice.

Hope that helps a little.

Dornak