Acceptable Schedules
One sensible “isolated, consistent” schedule:
- Run Xacts one at a time, in a series.
- This is called a serial schedule.
- NOTE: Different serial schedules can have different final states; all are “OK” -- DBMS makes no guarantees about the order in which concurrently submitted Xacts are executed.
Serializable schedules:
- Final state is what some serial schedule would have produced.
- Aborted Xacts are not part of schedule; ignore them for now (they are made to `disappear’ by using logging).