用proc SQL 吧

1# wenchongange




你最好是把原表放上来

Use the options ( nobs=last point=last) on set statement. The advantage is read 3 rows instead of 15 rows in the following example. It is much efficient.


28   data t1 t2 t3;
29      do i=1 to 3;
30         output t1;
31      end;
32       do i=1 to 5;
33         output t2;
34      end;
35       do i=1 to 7;
36         output t3;
37      end;
38   run;

NOTE: The data set WORK.T1 has 3 observations and 1 variables.
NOTE: The data set WORK.T2 has 5 observations and 1 variables.
NOTE: The data set WORK.T3 has 7 observations and 1 variables.
NOTE: DATA statement used (Total process time):
      real time           0.03 seconds
      cpu time            0.03 seconds


39
40   data lastrows;
41      set t1 nobs=last point=last;
42      output;
43      set t2 nobs=last point=last;
44      output;
45      set t3 nobs=last point=last;
46      output;
47      stop;
48
49      run;

NOTE: The data set WORK.LASTROWS has 3 observations and 1 variables.
NOTE: DATA statement used (Total process time):
      real time           0.01 seconds
      cpu time            0.01 seconds