what order are the steps done in a proc sort?

[cellurl1]

proc sort data=customer_barcode_account nodupkey;
by cust_nbr;
where cust_nbr gt 0;

to me, this is 3 steps.

Q: What are the order of the steps, say I was splitting it into three steps, not one.

[Tom · Accepted solution]

The WHERE statement filters the data into PROC SORT. 

The NODUPKEY option filters the data out of PROC SORT.

So the actual sorting is in the middle.

[cellurl1]

thanks