Control of sequence

Overview

In many applications the sequence of running programs is important.

Some data may be required before related data can be entered.

For Example

In an airline reservation system a flight must be entered before passengers can be entered.
Clients must be entered before they can be billed
Sales Areas must be defined before they can be used fro analysis
Employees must be entered before they can be paid

The sequence of enter batch, sort/validate, then update must be strictly followed.