A database has been defined in simple terms as a collection of related data. The most common database type is the relational database model that stores data in tables. The tables are further segregated into rows and columns. Categorization of the data is done in the columns while the rows represent individual entries of data. A database is managed via a group of programs that perform the function of creating as well as maintaining the database. The group of programs together are referred to as a DBMS (Database Management System).
The DBMS has also other functionalities like concurrency management, ensuring security of data in a database, make sure that the data is always integral, control the redundancy of data, creating back up for the data and also facilitating the interaction between the user and the database. With a database, there is a lot of efficiency in the storage as well as the retrieval of data. A database is managed by a database administrator. The DBA has the overall role of monitoring the activities of the users of the database and has all the privileges concerned with the database. The administrator will also issue rights and access permissions to users as they suit them. A database can also be contained in a local machine or can be distributed. It is integrated with other front end applications like web applications or desktop applications to make it easier for users to manage their data without having learnt the complex implementation details concerned with the development and maintenance of a database.
Entity Relationship Diagram
A database administrator is the overall manager of a database system. An administrator oversees that the database system achieves its maximum capability and is running on an optimum level. The DBA has to know exactly who are the users of a system so as to establish what data is relevant to them then provide only the required view to a given set of users. Accessibility of the database by the users has also to be ensured its taking place as required to prevent downtimes where some or all the users have no access to the database. The admin must also monitor how the database is performing so as to optimize its query processing for faster access, retrieval and posting of data into the database. The DBA will also be in charge of updating the database software and where necessary installing newer software to meet the changing trends in technology.
Privileges of users are also granted to them by the DBA who regulates access of data to users who are not supposed to view some confidential data. In case of failures the DBA will enable the backup plan so as to make sure that very critical information that may very necessary for the running of an organization is still available. Security of the database is also charged to the DBA who should ensure that the database is safe from unauthorised intruders and malicious computer programs that may want to access or damage data stored in the database. In accordance to some ever changing organizational needs, the DBA should be able to change the structure and design of the database so that it is in line with the changes that may have taken place in the organization. The DBA should also make sure that the database does not consume too much of resources e.g. disk space due to improper management.
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