subject: Database Management System And Its Administrator [print this page] A database manager, also referred to as a database administrator, is responsible for working with database management systems software in order to determine the best possible way to organize, update, modify and to store data. In order to properly perform this duty, a database manager must identify the requirements of the user database, create a database management system. The database manager must also monitor the system in order to guarantee proper performance. To guarantee the proper performance, the database manager needs to understand the platform used to run the database and must be able to add new users to the system. As such, the database manager is often also responsible for designing and implementing system security and other security measures.
Types of database systems
File Management System: The file management system in which all data is stored on a single large file. The main drawback in this system is searching a record or data takes a long time. Then also the FMS system had lot of drawbacks to name a few like updating or modifications to the data cannot be handled easily, sorting the records took long time and so on. All these drawbacks led to the introduction of the Hierarchical Database System.
Hierarchical Database System: The earlier system FMS drawback of accessing records and sorting records which took a lengthy time was removed in this by the introduction of parent-child relationship between records in database. The origin of the data is called the root from which several branches have data at different levels and the last level is called the leaf. The main drawback in this was if there is any modification or addition made to the structure then the whole structure needed to change which made the task tiresome one.
Network Database System: In this the main perception of many-many relationships got introduced. But this also followed the same technology of pointers to define relationships with a difference in this made in the introduction if grouping of data items as sets.
Relational Database System: In order to overcome all the drawbacks of the previous systems the relational database management System got introduced in which data get controlled as tables and each record forms a row with many fields or attributes in it. Relationships between tables are also formed in this system.
