Proc sort - order of non BY variables

[HeatherNewton]

Hi if i have a table with 10 column, and i asked to sort it by col a col b col c.
Lets say i have 3 cols where col a col b col c are the same, once the table us sorted by col a col b col c, how are the rest of the columns arranged? What does it based on?

[Kurt_Bremser]

The order of the observations within a group (as defined with BY) is usually that which existed before in the dataset, but this is not guaranteed, e.g. when data is read from a DBMS or SPD engines.

If a certain order is required, you have to force it.