SQLOBS is also useful when creating a series of macro var. For example:

proc sql noprint;
select distinct model
into :model1-
from sashelp.cars;
%let nummodels=&sqlobs;

Then you can write a %DO loop to loop through &nummodels as necessary to process other data using &&model&i (assuming i is your do loop var name).

This also employs the "trick" of creating a series of macro variables without knowing the ending number.