Data Logic

[Almoha]

All,

This is the data set I have

Id             res

111        YYY

111        XXX

111        NNN

222       YYY

222       YYY

222       NNN

222       XXX

222       PPP

222       XYZ

222       HAB

222        XCV

This is the dataset I am looking for (i.e the res should be missing for the records that are after first XXX)

Id             res

111        YYY

111        XXX

111      

222       YYY

222       YYY

222       NNN

222       XXX

222      

222      

222      

222     

Thanks

-Bhargav

[Reeza]

Create a flag and use RETAIN to hold it across rows. 

Data want; 

srt have;

by id;

retain flag;

if first.id then flag=0;

if flag=1 then call missing(res);

if res='XXX' then flag=1;

run;