Missing the last few column names when exporting to CSV file - sas

Question

I am trying to export a dataset in my Library/Work. It shows normal in SAS. However when I export the data as CSV or txt file (either from right click -> export, or use SAS code), the last few column names were missing (showing empty in CSV), while the values were kept. The column names missing are all in the format of "Log_xxx" but some the same-format columns were exported correctly. There're around 4000+ columns in my dataset.
The code I've tried is like:
proc export data=logdata
outfile="path.csv"
dbms=csv
replace;
run;
I've exported many datasets before, but it's the first time I have this kind of problem. I've tried to restart SAS and it's still not working.
I simply wanted to export the whole dataset completely with all column names and values.
Do you have any ideas?

Answer 1

I don't think it is PROC EXPORT that is the issue. You have to tell SAS that you want to write lines that are longer then 32,767 bytes (the default setting for the LRECL option).
This code works:
data test;
array longname [3500] ;
run;
filename csv temp lrecl=1000000 ;
proc export data=test dbms=csv file=csv ;
run;
So change your code to set the LRECL long enough for all of the variable names.
filename csv "path.csv" lrecl=1000000 ;
proc export data=logdata
outfile=csv
dbms=csv
replace
;
run;

Answer 2

Based on this post, your header is likely exceeding 32k characters, which causes the issues.
Solution is to manually create the file without proc export, or proc export to XLSX doesn't appear to have the issue.
*Create demo data;
data class;
set sashelp.class;
label age='Age, Years' weight = 'Weight(lbs)' height='Height, inches';
run;
proc sql noprint;
create table temp as
select name as _name_, label as _label_
from dictionary.columns
where libname="WORK" and upcase(memname)="CLASS";
select nliteral(name) into :varList separated by ' '
from dictionary.columns
where libname="WORK" and upcase(memname)="CLASS";
quit;
data _null_;
file "&sasforum.\datasets\TwoLinesHeader.csv" dsd lrecl = 40000;
set class;
if _n_ = 1 then do;
do until(eof);
set temp end=eof;
put _name_ #;
end;
put;
end;
put (&varList) (:);
run;