topic Combining datasets with different variable length using macro in SAS Programming

Combining datasets with different variable length using macro

aayo — Thu, 16 Apr 2020 21:05:39 GMT

Hello,

I am trying to combine imported datasets using macro but i get warning below

WARNING: Multiple lengths were specified for the variable A by input data set(s). This can cause
truncation of data.

Note that var A has different length format automatically assigned during the import procedure.

below is my code.

%macro combine;
data c;
set
%do i = 1 %to 2;
&library..&&file&i
%end;
;
run;
%mend;
%combine;

Re: Combining datasets with different variable length using macro

ghosh — Thu, 16 Apr 2020 21:51:19 GMT

Explicitly define the lengths of the offending variable(s) to their predetermined maximum value (eg. 60 chars)

%macro combine;
data c;
length problemvar $60;
set
%do i = 1 %to 2;
&library..&&file&i
%end;
;
run;
%mend;
%combine;

Re: Combining datasets with different variable length using macro

aayo — Thu, 16 Apr 2020 22:31:30 GMT

This works fine. Thanks much.

Re: Combining datasets with different variable length using macro

Kurt_Bremser — Fri, 17 Apr 2020 05:28:33 GMT

Do not fix this here, prevent it when the data is imported in the first place. Do not use proc import, use a custom data step to read data, where you control all variable attributes.

See Maxims 31 and 22. Avoid Excel Files, convert to CSV first.

Re: Combining datasets with different variable length using macro

aayo — Fri, 17 Apr 2020 23:21:51 GMT

Hi Kurt,

This is noted.

I have changed my import to data step and made use of csv file.

Thanks.