LINDA ADAM'S SAS TIPS

Modifying Data Sets and Variables Efficiently with PROC DATASETS

Data sets and variables can be modified using data steps or PROC DATASETS. Here are a few examples using each method, with the time they took to execute.

For this example, a dataset (sasuser.grads05) with 239,862 observations was created.

Modifying a Data Set
1. Using a data step:
Data sasuser.grads05 (label=’2004-05 Graduates’);
Set sasuser.grads05;
Run;

Real time: 1.45 seconds
CPU time: 0.18 seconds

2. Using PROC DATASETS:
Proc datasets lib=sasuser nolist;
Modify grads05 (label=’2004-05 Graduates’);
Quit;
Run;

Real time: 0.01 seconds
CPU time: 0.01 seconds

Modifying Variables
1. Using a data step:
Data sasuser.grads05;
Set sasuser.grads05(rename=(sex=gender));
Format dtupdate mmddyy10.;
run;

Real time: 2.91 seconds
CPU time: 0.19 seconds

2. Using PROC DATASETS:
Proc datasets lib=sasuser nolist;
Modify grads05;
Rename sex=gender;
Format dtupdate mmddyy10.;
Quit;
Run;

Real time: 0.02 seconds
CPU time: 0.02 seconds

Click here to learn more about PROC DATASETS.

posted by Linda J. Adams @ 2:25 PM