WEEK 11 - DBMS (advantages & disadvantages)

Advantages of DBMS
1) Reduction of Redundancies - avoid unnecessary duplication data and minimizing the storage of data.
2) Sharing Data - allows the sharing of data under its control by any number of application and users.
3) Data Integrity - data contained acurate and consistency.
4) Data Security - ensure that proper access procedures are followed, including proper authentication schemes for access to DBMS and additional checks before permitting access to sensitive data.
5) Conflict Resolution - permitting less critical applications to continue to use the database.
6) Data Independence - allows changes in the physical storage devices

Disadvantages of DBMS

A significant disadvantage of the DBMS system is cost. In addition to the cost of purchasing ordeveloping the software, the hardware has to be upgraded to allow for the extensive programs and the workspaces required for their execution and storage. The processing overhead introduced by theDBMS to implement security, integrity, and sharing of the data causes a degradation of the responseand through-put times. An additional cost is that of migration from a traditionally separateapplication environment to an integrated one.

While centralization reduces duplication, the lack of duplication requires that the database beadequately backed up so that in the case of failure the data can be recovered. Backup and recoveryoperations are fairly complex in a DBMS environment, and this is exacerbated in a concurrent multiuser database system. In further a database system requires a certain amount of controlledredundancies and duplication to enable access to related data items.Centralization also means that the data is accessible from a single source namely the database. Thisincreases the potential severity of security breaches and disruption of the operation of theorganization because of downtimes and failures. The replacement of a monolithic centralizeddatabase by a federation of independent and cooperating distributed databases resolves some of theproblems resulting from failures and downtimes.