Programatically determine if a variable exists in a data set

Use the OPEN and VARNUM functions to determine if a variable exists in a SAS data set. The OPEN function opens a SAS data set and returns a data set identifier. The VARNUM function returns the variable’s position in the data set. If the variable does not exist then VARNUM returns a 0.

/* Create sample data */

data test;

input fruit $ count;

datalines;

apple 12

banana 4

coconut 5

date 7

eggs 9

fig 5

;

/* Specify the data set to open in the OPEN function.  Specify the  */

/* variable to be located in the second parameter of the VARNUM     */

/* function. If the variable does not exist, the value of check     */

/* will be zero.                                                    */

%let dsid = %sysfunc(open(test));

%let chk = %sysfunc(varnum(&dsid, count));

%let rc = %sysfunc(close(&dsid));

%put &chk;

There is another Method with a datastep explained at SAS’s website ( http://support.sas.com/kb/26/003.html)