I'm new to sas so this is probably dumb question. I have two tables, one is just a template that has every possibility. The second is a subset of that template with the data filled in. I want to merge the two so I keep all the rows but fill in the data where available. Any ideas.
If your table 1 does not have duplicates of the Key variable and both table 1 and table 2 are sorted by the key then:
data newtable;
update table1
table2
;
by key;
run;
Note that table2 can have multiple records with the same key variable(s) and all of the values will be used to update the single record in table1 with that Key.