Macro to count records in multiple datasets

[sashelp123]

Hello, I am having an issue with something in SAS (version 9.4) and could use some expertise! Basically my macro currently looks like this:

proc sql;

select count(*) into: thirtyfive_counts

from history_upi, dummy_upi_clean, dummy_upi_76, history_upi_76;

quit;

%macro yyy(when);

%if &when ne 0 %then %do;

%include 'G:\Groups\HHR\new 35 file.sas';

%end;

%mend;

%yyy(&thirtyfive_counts);

Ultimately, I want this program(in the include statement) to be run if there are any records in any of those 4 datasets (listed in the from statement). The issue I am having is if one of those datasets is empty (which will sometimes be the case) it is giving me an error and not running the program. However, if I only list the datasets where this is a record, it will work fine. I would like it to run if there is an observation in any of the four datasets. Is this possible?

Thanks!

[Kurt_Bremser]

%let thirtyfive_counts=0;
proc sql no print;
select sum(nobs) into: thirtyfive_counts
from dictionary.tables
where libname = 'WORK' and lowercase(memname) in
("history_upi","dummy_upi_clean","dummy_upi_76","history_upi_76");
quit;

is the correct way to determine this. If none of these datasets exists, you still get a zero.