Data integrity is the ability of the system to keep itself not only internally consistent but also to maintain external consistency. Internal consistency is maintained through referential integrity. Referential Integrity means simply that rows may no be deleted from tables if there are other tables that depend on that row. If a customer master record (the unique identifier of a customer) exists then it cannot be deleted if there are open orders for that customer. Many systems rely on the database management system to maintain referential integrity. This approach has one significant ease of use limitation. If you elect to delete a record you do not know until after you start the update process if the delete is allowed. Once again you will receive the irritating and aggravating “transaction not allowed” message. The AMAPS+PLUS Intelligent GUI identifies if records may not be deleted and indicates so by disabling the “Delete” button.
The second area of data integrity maintenance relates to external consistency. AMAPS+PLUS addresses the external consistency issue three ways. First, templates or profiles are used to customize data entry to the user’s needs. These templates control the valid sub set of values displayed in combo boxes. If, for example, the list of allowed values was AA, BB, CC, DD, and EE then a template could constrain this list to AA and EE based on attributes of the data being entered. Profiles, also, perform range checking to make sure that numeric values fall within a set of parameters. The values, for example, must be greater then or equal to three and less than or equal to seven.
Second, all AMAPS+PLUS data is both rigorously edited to make sure it within user prescribed values and validated. The validation process protects against the most harmful data entry errors. If, for example, a Customer Ordered is entered then the validation process ensures that the customer identified on the order exists.
Third AMAPS+PLUS provides comprehensive audit trails that record data changes. The Audit trail is the last line of defense. This trail shows the data value, who entered the data and the date and time of entry. This facility lets you track down the source of data and take appropriate corrective action.