1. Centralized Database :
A centralized database is basically a type of database that is stored, located as well as maintained at a single location only. This type of database is modified and managed from that location itself. This location is thus mainly any database system or a centralized computer system. The centralized location is accessed via an internet connection (LAN, WAN, etc). This centralized database is mainly used by institutions or organizations.
- Since all data is stored at a single location only thus it is easier to access and co-ordinate data.
- The centralized database has very minimal data redundancy since all data is stored at a single place.
- It is cheaper in comparison to all other databases available.
- The data traffic in case of centralized database is more.
- If any kind of system failure occurs at centralized system then entire data will be destroyed.
2. Distributed Database :
A distributed database is basically a type of database which consists of multiple databases that are connected with each other and are spread across different physical locations. The data that is stored on various physical locations can thus be managed independently of other physical locations. The communication between databases at different physical locations is thus done by a computer network.
- This database can be easily expanded as data is already spread across different physical locations.
- The distributed database can easily be accessed from different networks.
- This database is more secure in comparison to centralized database.
- This database is very costly and it is difficult to maintain because of its complexity.
- In this database, it is difficult to provide a uniform view to user since it is spread across different physical locations.
Difference between Centralized database and Distributed database :
|S.NO.||Centralized database||Distributed database|
|1.||It is database that is stored, located as well as maintained at a single location only.||It is a database which consists of multiple databases which are connected with each other and are spread across different physical locations.|
|2.||The data access time in case of multiple users is more in a centralized database.||The data access time in case of multiple users is less in a distributed database.|
|3.||The management, modification and backup of this database is easier as entire data is present at the same location.||The management, modification and backup of this database is very difficult as it is spread across different physical locations.|
|4.||This database provides a uniform and complete view to the user.||Since it is spread across different locations thus it is difficult to provide a uniform view to the user.|
|5.||This database has more data consistency in comparison to distributed database.||This database may have some data replications thus data consistency is less.|
|6.||The users cannot access database in case database failure occurs.||In distributed database if one database fails users have access to other databases.||7.||Centralized database is less costly.||This database is very expensive.|