How to merge 19 datasets into one

[Denali]

Hi,

I have collected patients demographic characteristics for 19 months (from Dec. 2016-June 2018). Each month has its own dataset and the patients are not likely to be same people. Each dataset contains patient ID, sex, race, each month we approximately have 500-1000 patients.

How do I combine these 19 datasets into one? Writing the merge statement for 10+ times or sql? Any better idea? Thank you!

[Kurt_Bremser]

You do not merge those datasets, but stack them, and add a variable for the period (SAS date preferred). The resulting vertical (long) dataset will be ideal for further processing.

[Denali]

I added a variable called "Month" so it will be 1-19 month when I stack them. My question is how do I easily stack 19 datasets?

Should I use "set" for 18 times?

[Kurt_Bremser · Accepted solution]

Only one set, and if you have clever names, you can use a wildcard:

data want;
set mydata:;
run;

eg if your datasets were work.mydata1 to work.mydata19.