List Customers

Listing customers is described in the above diagram. The user selects a specific criterion from a list of available criteria and passes this to the system. Customers corresponding to this criterion are then retrieved from the Customer datastore and returned to the user.

Reports may be generated based on the aforementioned criteria. This simplification of the system allows for generated reports that correspond directly to the information that the user wishes to view. For example, when the user selects the criterion that lists customers "By Daily Route", a report can be generated directly from the information that is returned to the user simply using the print features of the system.

The returned status corresponds to the success of the operation. If customers are successfully retrieved from the datastore, the status returns Successful. If customers corresponding to the selected criterion do not exist, the corresponding error message is returned.

P-Spec

Process ID	1.A.5
Process Name	List Customers
Inputs	customer criteria
Outputs	customers
Permissible User	Administrator, Salesperson
Assumptions	All information entered is syntactically correct.
Error Conditions	The criteria entered is not a valid criteria.

Data Elements (Data Dictionary)

Name	customer criteria
Kind	Data movement in DFD
Type	Integer
Description	This data element corresponds to an integer that is used to specify the type of information that is to be displayed. For example, criteria 2 may display only a particular user's 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	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.