>>Paul Dorfman wrote >><<< >>1) Observations from the end of one or more input data sets will be >>deleted from the output data set unless all input data sets have the >>same number of observations. >

It was me, and that's because in a test I ran that's what happened...

1 data a b c ; 2 do i = 1 to 10 ; 3 if i <3 then output a ; 4 if i < 6 then output b ; 5 output c ; 6 end ; 7 run ;

NOTE: The data set WORK.A has 2 observations and 1 variables. NOTE: The data set WORK.B has 5 observations and 1 variables. NOTE: The data set WORK.C has 10 observations and 1 variables. NOTE: DATA statement used: real time 0.03 seconds cpu time 0.03 seconds

8 9 data final ; 10 set a ; 11 set b ; 12 set c ; 13 run ;

NOTE: There were 2 observations read from the data set WORK.A. NOTE: There were 2 observations read from the data set WORK.B. NOTE: There were 2 observations read from the data set WORK.C. NOTE: The data set WORK.FINAL has 2 observations and 1 variables. NOTE: DATA statement used: real time 0.05 seconds cpu time 0.06 seconds 2

The resulting output data set WORK.FINAL has 2 observations, which is less than the number of observations in input data sets WORK.B and WORK.C. That's what I meant to post, and I'm sorry it didn't come across clear.

Paul McDonald pdm@spikeware.com -------------------- Free SAS Training and Newsletter http://www.spikeware.com/