macro variable not being resolved correctly in SAS

Question

I have a SAS macro like this:

%macro test;
proc sql;
SELECT count(*) INTO:Nbr_Obs from table1;
quit;
%put  observations=&Nbr_Obs;
%if &Nbr_Obs=0 %then %do;
proc sql;
  drop table table1 ;
quit;
%end;
%mend;

Neither the %put statement is showing up in the log, and the 'if' condition is always evaluating to true. How can I resolve this?

EDIT: This is what I see in log:

MPRINT(TEST):   proc sql;
MPRINT(TEST):   SELECT count(*) INTO:Nbr_Obs from TABLE1;
MPRINT(TEST):   quit;
observations=
...
...

And after this, it shows that SQL is executing. So it seems that the PU T statement is executing before the SQL?

Answer 1

It is always a best practise to strip leading and trailing blanks from macro variables created using INTO clause, this is the reason for incorrect comparison. Please modify as below,

%macro test;  

   proc sql;
     SELECT count(*) INTO:Nbr_Obs 
     from table1;
   quit;  

   %let Nbr_Obs=&Nbr_Obs; * Strips blanks;  
   %put  observations=&Nbr_Obs;  

   %if &Nbr_Obs=0 %then %do;  
     proc sql;  
       drop table table1 ;  
     quit;  

   %end;  

%mend;