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•  Sharing of Data: It means data can be accessed by multiple users at the same time. Different users can have different
          rights and privileges to access data. Some may have the right to only view the data. Some may have permission to
          modify the data. These rights and privileges for sharing the data through a centralized system is taken care of by
          database administrators.
        •  Data Integrity: Data integrity means that the data is accurate and consistent in the database. Data is validated
          thoroughly using data integrity constraints so that correct data is entered in a database. It is also very important
          since the data is used by multiple users.
        •  Data Security: DBMS provides data security so that only authorised users can have access to the database. For
          security reasons different users have  different privileges. Also,  users are  assigned  user ids  and  passwords for
          authorised access to the centralised database.
        •  Privacy: Since the database provides access to the authorised users, privacy plays a very important role. Different
          users will have access to different components of the database depending on the role of the user. Some may have
          access only to view the data. Others are allowed to do changes in a few databases while others are the main
          administrators of the whole database system.
        •  Data Backup and Recovery: DBMS provides data backup and recovery features. User can maintain data backup on
          weekly or fortnightly so that if data loss occurs due to system failure then data recovery process can be easily carried out.

        Features of Database

        The main features of a database are as follows:
        •  There can be more than one table in a database. For example, in a school, in the Students’ database, there can be
          one table for saving general details about the student. Another table may be to save the marks and progress of the
          student. Other tables may include, fee details, library books issued, etc. all related to the student.
        •  The information stored in a table in a database relate to one specific topic. So, all the related information on a topic
          can be viewed in one single table.
        •  In a database, data can be simultaneously accessed by many users. So, it saves storage space by storing one table at
          one place from every authorised user can access it.
        •  Database offers data protection and features like recovery and backup for easy recording and retrieval of data.
        •  Database allows the users to views data in different views with the required information only.
        •  Data stored in a database remains permanently stored till the time it is manually deleted from the system/ server.
        •  If the database table has unique value field than there are minimum, chances of duplication of data which avoids
          confusion at a later stage.


                ELEMENTS OF A DATABASE

        Some of the important elements of a database are as follows:
        •  Database Management System: Data is logically organised in a Database so that it can be created and maintained
          efficiently. The software that deals with the creation, updation and retrieval of data from the database is known as
          Database Management System. If this data is accessed by multiple users then the database management system
          provides data consistency and data security. It also provides a user-friendly interface so that database objects like
          tables, queries, forms and reports help in easy access and storage of data with different data constraints.
        •  Database: A database is made up of one or more related tables. It is like a container that holds tables and other
          objects like forms, queries and reports. For example, School is a database where tables like- Student Personal Details,
          Marks details in different tests, final result, etc will be stored. Another database will be Library - with the tables like
          Books in stock, Books issued, Books ordered, Books lost/damaged.
        •  Table: Table is a collection of related data stored in the form of rows and columns. It contains information about one
          type of item.
        •  Record/Row: A row is a collection of data values that forms a complete information arranged horizontally. It is also
          known as a record in a table.
        •  Column/Field: The Columns are vertically arranged and store data of similar type. Each column has a column
          heading and a data value of the same type. It is also known as a Field in a table.


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