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Advantages consolidating databases

advantages consolidating databases-61

Blogger: Marcus Collins In my recent post I detailed key points organizations should consider when embarking on a database consolidation initiative.

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The application programmer can also identify integrity constraints in the program code during developing the application program.If a data item appears only once, any update to its value has to be performed only once and the updated value (new value of item) is immediately available to all users.If the DBMS has reduced redundancy to a minimum level, the database system enforces consistency.The constraints may be applied to data item within a single record or they may be applied to relationships between records.Most of the DBMSs provide the facility for applying the integrity constraints.Sometimes, it is necessary to create duplicate copies of the same data items in order to relate tables with each other.

By controlling the data redundancy, the data consistency is obtained.

The integrity constraints are automatically checked at the time of data entry or when the record is updated.

If the data entry operator (end-user) violates an integrity constraint, the data is not inserted or updated into the database and a message is displayed by the system.

The recommended process is shown schematically below: The Burton Group Structured Approach to Database Consolidation (SADC) takes a series of inputs and, through a complex tradeoff analysis, outputs a plan for a detailed analysis phase followed by the execution of a series of phased consolidations.

The tradeoff analyses take the set of possible consolidation scenarios (i.e., schema-to-database and database-to-server combinations) and use the business objectives and constraints (i.e., prioritized tradeoff criteria) to determine the optimal consolidation scenario.

It means that when a data item appears more than once in the database and is updated, the DBMS automatically updates each occurrence of a data item in the database.