Vtype Function/If-then-Else condition/PUTN function

[keen_sas]

Hi All , I am using VTYPE and PUTN function in IF-THEN-ELSE condition ,output is fine , but have a doubt in the execution as below, since it is throwing a NOTE in the log ,which should not happen.

data want;
 set sashelp.rent; 
 if vtype(date)='N' then mdate=putn(date,vformat(date));
 else if vtype(date)='C' then mdate=scan(date,1,'T');
run ;


NOTE: Numeric values have been converted to character values at the places given by: (Line):(Column).
      26:42   
NOTE: There were 10 observations read from the data set SASHELP.RENT.
NOTE: The data set WORK.WANT has 10 observations and 3 variables.
NOTE: Compressing data set WORK.WANT increased size by 100.00 percent. 
      Compressed is 2 pages; un-compressed would require 1 pages.


Concern: As per the data, the DATE variable is numeric and it is getting satisfied in the first 
IF condition. But why it is checking for second ELSE IF condition and throwing a NOTE 
(Numeric conversion) in the log. Similarly in the below condition also , 
when the first IF condition is not satisfied but still executing with a NOTE (Character conversion )
 in the log .Ideally it should not happen , what could be the issue for this if-then-else conditions 
and how to resolve it with out any CONVERSION notes in the log. 

data want1;
 set want;
 if vtype(mdate)='N' then mdatenew=putn(mdate,vformat(mdate));
 else if vtype(mdate)='C' then mdatenew=mdate;
run ;


NOTE: Character values have been converted to numeric values at the places given by: (Line):(Column).
      25:41   
NOTE: There were 10 observations read from the data set WORK.WANT.
NOTE: The data set WORK.WANT1 has 10 observations and 4 variables.
NOTE: Compressing data set WORK.WANT1 increased size by 100.00 percent. 
      Compressed is 2 pages; un-compressed would require 1 pages.

[s_lassen]

Your problem is that the statements for the character assignment and PUTN function is still in the code, even though they do not get executed. The notes you get are compile-time, and the compiler does not check if the code will be executed, it just compiles it.

You will either have to live with it (I would probably avoid such notes in production jobs), or do something else. 

[Patrick]

Agree with @s_lassen 's explanation and also that we should avoid such conversion notes BUT: I feel your case here is the exception to the rule. It's just a compiler Note and there isn't actually such a conversion happening. So in your case just adding a comment to the code which explains the SAS note and that it's a non-issue would be good enough for me for production worthy code.

Question: What should happen if there is no format attached to the variable?