Detailed Design Document (Delete Customer)

Deleting a customer is described in the above diagram. The user passes the customer ID to the system. The system checks to see if the corresponding customer possesses any pending orders by checking the Order datastore before flagging the customer as inactive (deleted). The system then updates the position number of the remaining active customers in the Customer data store.

The returned status corresponds to the success of the operation. If the customer is successfully flagged as deleted in the customer datastore, the status returns Successful. If the customer has any pending orders, the user is notified of this condition and has the option of deleting the pending orders before deleting the customer from the Customer datastore.

P-Spec

Process ID	1.A.4
Process Name	Delete Customer
Inputs	customer ID
Outputs	None
Permissible User	Administrator
Assumptions	All information entered is syntactically correct.
Error Conditions	The customer ID entered does not exist.

Data Elements (Data Dictionary)

Name	customer
Kind	Data movement in DFD
Type	Instance of an Entity
Description	This data element corresponds to a complete instance of the Entity Customer.

Name	customer ID
Kind	Primary Key
Type	Integer
Description	A primary key attribute of entity Customer. The maximum length is exactly 8 digits long. The format is the type integer. For example: 78437893 The primary key represents a unique customer. This unique ID is used to distinguish between the customers.

Name	customers
Kind	Data movement in DFD
Type	Instance of an Entity
Description	This data element corresponds to one or more complete instances of the Entity Customer.

Name	orders
Kind	Data movement in DFD
Type	Instance of an Entity
Description	This data element corresponds to one or more complete instances of the Entity Order.

Name	status
Kind	Data movement in DFD
Type	Return Message
Description	This data element corresponds to an error message being returned from an operation. An error message may be both successful and unsuccessful. Unsuccessful error messages are further subcategorized into different errors based on the possible errors that can occur in an operation.