update

[SASPhile]

When importing data, the some of zip and ndc numbers are imported as '0' instead of their values.This happened after many loads.
How do I update/replace the dataset where the zip ad ndc numbers are '0''s with their original values.I have a dataset where I have the actual values.
I tried update as follows:
data final;
update spdata(where=provider='MEDCO' and file_date='2009-04)) zip_ndc;
by patient_id;
run;

zip_ndc has three variables:patient_id zip and ndc.
When I use patient_id in the by statement , it fails saying that there are multiple values under the by group.

[sbb]

Possibly consider a MERGE or MODIFY. From the SAS support http://support.sas.com/ here is a technical document on the MODIFY statement in the DATA step processing. You must determine what SAS variables represent a sufficiently granular key (BY statement variable list) to perform the master file update.

Scott Barry
SBBWorks, Inc.

TS-250
DATA Step Programming Using the MODIFY Statement
http://support.sas.com/techsup/technote/ts250.html