The APPEND procedure adds the observations
from one SAS data set to the end of another SAS data set.
Generally, the APPEND
procedure functions the same as the APPEND statement in the DATASETS
procedure. The only difference between the APPEND procedure and the
APPEND statement in PROC DATASETS is the default for
libref in
the BASE= and DATA= arguments. For PROC APPEND, the default is either
WORK or USER. For the APPEND statement, the default is the libref
of the procedure input library.