topic Re: SET multiuple data sets in SAS Programming

SET multiuple data sets

Ronein — Tue, 07 Sep 2021 07:36:15 GMT

Hello,

I want to ask about concatenate data sets.

What is the difference between Way2 and Way3 ?

Is Way3 correct ?

Is it essential to use macro with DO (Way2) ?

 data tbl1;
 input a;
cards;
1
2
3
;
run;

data tbl2;
input a;
cards;
4
5
6
;
run;


/*Way1*/
data wanted;
set tbl1 tbl2;
run;

/*Way2*/
%macro combine;
data wanted;
  set
  %do i = 1 %to 2;
   tbl&i
  %end;
  ;
run;
%mend;
%combine;

/*Way3*/
data wanted;
set
do i = 1 to 2;
tbl&i
end;
;
run;

Re: SET multiuple data sets

Kurt_Bremser — Tue, 07 Sep 2021 09:23:43 GMT

1 and 2 create identical code, so they are equivalent; 2 has the advantage that you can easily make the number of datasets dynamic.

3 is syntactically incorrect and will never work.

If you always have only two datasets, use method 1. Method 2 adds unneeded complexity that makes the code harder to maintain, in that case.

@Ronein wrote:

Hello,

I want to ask about concatenate data sets.

What is the difference between Way2 and Way3 ?

Is Way3 correct ?

Is it essential to use macro with DO (Way2) ?
 data tbl1;
 input a;
cards;
1
2
3
;
run;

data tbl2;
input a;
cards;
4
5
6
;
run;


/*Way1*/
data wanted;
set tbl1 tbl2;
run;

/*Way2*/
%macro combine;
data wanted;
  set
  %do i = 1 %to 2;
   tbl&i
  %end;
  ;
run;
%mend;
%combine;

/*Way3*/
data wanted;
set
do i = 1 to 2;
tbl&i
end;
;
run;

Re: SET multiuple data sets

Ronein — Tue, 07 Sep 2021 11:51:22 GMT

Thanks, may you please explain why way3 is incorrect?

Re: SET multiuple data sets

PaigeMiller — Tue, 07 Sep 2021 12:17:56 GMT

Already explained by @Kurt_Bremser who said it is syntactically incorrect. You cannot have DO in a SET statement.

Re: SET multiuple data sets

ballardw — Tue, 07 Sep 2021 14:58:04 GMT

@Ronein wrote:
Thanks, may you please explain why way3 is incorrect?

Run the code.

Read the error messages.

Re: SET multiuple data sets

Tom — Tue, 07 Sep 2021 15:49:29 GMT

If you have more than two of these numbered datasets then use a dataset list in the SET statement.

set tbl1-tbl5 ;

Or the upper bound for the number of dataset varies.

%let n=5;
....
set tbl1-tbl&n;

Re: SET multiuple data sets

yabwon — Tue, 07 Sep 2021 19:11:31 GMT

Or if you have "many" data sets with "non-sequential suffix" you can make it:

set tbl: ;

so all data sets with the "tbl" prefix will be included.

And by using the "indsname=" option you can get the name of all data set read int a variable:

data want; set tbl: indsname=indsname ; tbl_name = indsname; run;

All the best

Bart