proc contents data=sashelp.class;
run;
这里会有变量位置，类型，长度等信息

%macro vtype(lib=,ds=);
proc sql;
create table vtype as
select libname, memname, name, type
from dictionary.columns
where libname="&lib" and memname="&ds"
;
quit;
%mend;
%vtype(lib=SASHELP,ds=CLASS)