WARNING: FIRSTOBS option > number of observations in WORK.CLASS.

[data_null__]

I'm doing a typical look ahead read when the input data has only one observation I get the WARNING:.  My program still works I just don't want to be warned.

data class;
   set sashelp.class;
   output;
   stop;
   run;

data next;
   set class end=eof;
   if not eof then set class(firstobs=2 keep=name rename=name=nextname);
   output;
   call missing(nextname);
   run;
proc print;
   run;

34         data next;
35            set class end=eof;
36            if not eof then set class(firstobs=2 keep=name rename=name=nextname);
WARNING: FIRSTOBS option > number of observations in WORK.CLASS.
37            output;
38            call missing(nextname);
39            run;

NOTE: There were 1 observations read from the data set WORK.CLASS.
NOTE: The data set WORK.NEXT has 1 observations and 6 variables.
NOTE: DATA statement used (Total process time):
      real time           0.01 seconds
      cpu time            0.00 seconds

[Tom · Accepted solution]

I don't know of any option to suppress that warning.

You could perhaps use a view to create the look_ahead data.

data class;
   set sashelp.class (obs=1);
run;

data look_ahead / view=look_ahead;
  set class ;
  if _n_ > 1;
  keep=name;
  rename name=nextname;
run;

data next;
   set class end=eof ;
   if not eof then set look_ahead ;
   output;
   call missing(nextname);
run;

Or if it doesn't mess up other things (like FIRST. processing) you could just read the first observation twice and throw away the extra one.

data next;
   set class(obs=1) class end=eof;
   if not eof then set class(keep=name rename=(name=nextname));
   if _n_ > 1 then output;
   call missing(nextname);
run;

[data_null__]

---

@Tom wrote:

I don't know of any option to suppress that warning.

You could perhaps use a view to create the look_ahead data.

data class;
   set sashelp.class (obs=1);
run;

data look_ahead / view=look_ahead;
  set class ;
  if _n_ > 1;
  keep=name;
  rename name=nextname;
run;

data next;
   set class end=eof ;
   if not eof then set look_ahead ;
   output;
   call missing(nextname);
run;

Or if it doesn't mess up other things (like FIRST. processing) you could just read the first observation twice and through away the extra one.

data next;
   set class(obs=1) class end=eof;
   if not eof then set class(keep=name rename=(name=nextname));
   if _n_ > 1 then output;
   call missing(nextname);
run;

---

Thanks Tom, excellent use of view and turning the problem around.  

[Ksharp]

John King, 
Can you add one more obs at the end of CLASS ?


data class;
   set sashelp.class (obs=1);
run;

data copy_class;
 set class(keep=name) end=last;
 output;
 if last then do;
  call missing(name);
  output;
 end;
run;

data next;
   set class end=eof;
   if not eof then set copy_class(firstobs=2 keep=name rename=name=nextname);
   output;
   call missing(nextname);
   run;