How to replace a column's value from another dataset

[cosmid]

Hi,

If I have two datasets, One and Two, both has a column named ID, how do I replace One's ID with Two's ID for just first 10 observations, ignoring all other vars?

Thanks!

[Tom · Accepted solution]

Sounds like crazy thing to do.

data want;
  merge one two(keep=id obs=10);
run;

[cosmid]

Oops...it seems that method didn't work. Instead of replacing the first 10 IDs it added 10 rows with the CMIDs fro the second dataset Two to the first dataset, One. 

[cosmid]

It worked. I am an idiot. For some reason I used SET instead of MERGE. Sorry for spamming.

Thanks for the help!

[Tom]

If you want to use SET then add an IF statement.

data want;
  set one;
  if _n_ <= 10 then set two(keep=id);
run;

[cosmid]

Wow! Thanks! It would be nice if I can do that with SAS. A MERGE with and without BY confuses me enough, lol. I need to get more practice for sure. Thanks again for teaching me the trick with the use of SET!