Insert Into when field does not exist in table inserting into

[LisaSAS]

I have a unique situation, I have 2 tables, one is getting created dynamically and the other is the table I want to insert my data into. My problem is the dynamic table one time might only I have 10 fields and the next time it could have 20 fields. I want to be able to just add the record with blank or nulls in the fields where I do not have in my dynamic table. Can this be done automatically?
INSERT INTO TableA
SELECT *
FROM TableB

My thoughts were I could just to a SELECT *, but then I get the error about missing fields.

[Tom · Accepted solution]

Why use INSERT?  Why not just use PROC APPEND.

proc append base=a data=b force;

run;