Centralized Database System 
 
　　There are some real advantages in a centralized database system；

1 ．Consistency
　　It's easier to avoid multiple listing of individual pieces of data-and the possible inconsistency so introduced-if a central programming group has control of all data entry.

2.Retrievability   
　　A central controlling group can make certain that all data entry follows a standard format and that the accessing of information also follows a standard and compatible format-all of which makes it very unlikely that any data will simply disappear。

3. Data Independence．   
　　User applications should be immune to possible changes in data storage and access methods. This immunity is easier to achieve if a central programming group is in control of all internal-clever and conceptual-level storage and all user interfaces with the conceptual level．If the system gives all these important advantages, one might wonder if there is any alternative to the centralized system－that is，any reason to choose a decentralized system? There is one：   
　　A centralized system is efficient, but it may note responsive to user needs．This is particularly tureen large organizations- the worldwide meteorological network, for example. Data- gathering methods in the Himalayas, the equatorial jungles，and the North African desert are different in every possible way. It’s reasonable to believe that the best choices for the corresponding data storage and access structure sought to be just as different. A centralized databases stem would not accommodate such differences.

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