The Database Idea Some General Principles General Principles

The Database Idea Some General Principles

General Principles þData has uses þStore once, access many times þData life cycle þData integrity þData auditing

Data Uses þ The database has to be o o o DEFINED CREATED ADMINISTERED, EVALUATED POPULATED (THROUGH FORMS) DISPOSED OF Database Administration Functions þ The data in the database has to be o ACCESSED THROUGH QUERIES o INTEGRATED INTO REPORTS o UPDATED BASED ON TRANSACTIONS Database User Functions

Store Once, Access Many Times Accesses and updates through billing cycle Accounting Sales Customer Info Data Base Creates customer record after initial sale Only needs to access to find out where to ship Shipping Service Accesses sales info for recalls; updates after service for billing

Data Life Cycle Database Administration Data Base Initial data entry Queries Updates Reports, analyses Disposal

Data Integrity þ There are levels of activity: o o o Definition Creation Access Update Maintenance Disposition þ Only certain processes and their owners and operators have specific levels of access þ Access levels can apply to any part of the data base þ Violations of data integrity are expected and procedures are in place to re-create integrity

Data Auditing þ All activity is tracked þ Violations of integrity result in alarms and hence in a variety of defensive behaviors þ Audit reports are produced regularly þ Certain agencies care about auditing