SAS select columns conditionally based on the table name

[eagles_dare13]

I have a proc step like this:

       proc print data=&tbl_name uniform label;

      var col_1 col_2 col_3;

          run;

          This step runs in a loop and every iteration picks up a different value of a tbl_name which is actually the name of a SAS table.

What I wish to do is:

      proc print data=&tbl_name uniform label;

     if &tbl_name = 'cust_table'  then

       var cust_id cust_name;

      else  if &tbl_name = 'salary_table'  then

        var amount currency;

        else

        /*if the tbl_name does not match any if condition above, then by default select all columns*/

         run;

How to do this?  I cannot find the syntax, I am just starting to learn  SAS.

[ballardw]

If this is running within a macro then use macro conditional logic:

      proc print data=&tbl_name uniform label;

     %if &tbl_name = cust_table  %then %do;  /* this comparison will be case sensitive so make sure it matche OR use %upcase(&tbl_name) = CUST_TABLE if you have doubts about case of tbl_name. NOTE: the macro processor pretty much treats everything as a string and quotes to delimit a string in simple comparisons like this are not needed*/

       var cust_id cust_name;

     %end;

      %else  %if &tbl_name = salary_table  %then %do;

        var amount currency;

      %end;

               /*if the tbl_name does not match any if condition above, then by default select all columns*/

         run;

[eagles_dare13]

Thank you.

I get error:

ERROR: Required operator not found in expression: upcase(&tbl_name) = cust_table

[ballardw · Accepted solution]

You would need the macro version of upcase %upcase(&tbl_name) = CUST_TABLE. I think the forum software split the line in my previous post at the % for some unknown reason or my typing isn't quite right this morning.

Anyway make sure if you use an uppercase comparison that the value compared is in uppercase.

[eagles_dare13]

Thank you. Can you please explain a bit why we need this % sign? What is the rule? If I am writing a macro, every keyword needs to be preceded with a % sign? Why the 'var' keyword does not need a % sign?

[ballardw]

The macro processor is a text generator. So any functions used by the processor use % to let the processor know this is a macro function. A confusing code but legal would be something like %if %upcase(&var) = VALUE %then upcase(something);

In your case, the "var" statement is normal SAS code that results with the condition. The bits between the %do; %end; are the results the macro processor passes to SAS as code to execute. The section could be multiple lines and even multiple procedure calls.

There are quite a few examples of macro coding in the online help and reasonably good documentation in the Macro Language:Reference under the Base SAS documentation.

[eagles_dare13]

Thank you very much!