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Relational Database: It is a type of database that stores
                     data  in  several  tables  and  links  those  tables  together
                     through  keys  that  allows  efficient  data  retrieval  and
                     reduced redundancy. Commonly used relational database
                     systems are LibreOffice Base, Microsoft Access, etc.
                   Clickipedia                                                               Relational Databases



                    The  relational  database  was  proposed  by  Edgar F.  Codd.  He  gave  a  set  of  thirteen rules
                    (Codd’s rules) to define a Relational Database Management System.


                      ADVANTAGES OF A DATABASE SYSTEM

                  A database system has many advantages. Some of the important advantages are:

                      It minimises the redundancy of data by organising data in a structured manner. This ensures
                     that data is not unnecessarily repeated across tables.
                      It saves the storage space.

                      All the users are provided with some access rights or privileges and permissions.
                      The files can be easily updated whenever changes are being made.

                      TERMS RELATED TO A DATABASE

                  Data is stored in the table of a database, as shown in below diagram.


                                                                    FIELDS

                                Reg No.         Name            Father’s Name        Date of Birth      Class
                                187/11    Aashi Kant           Mr. P.S. Kant       15/08/2007             VIII
                          RECORDS  156/12  Nazia Sharma        Mr. R.K. Sharma     22/10/2008             IX


                                                               Mr. V.S. Patel
                                          Rajesh Patel
                                194/11
                                                                                   16/04/2008
                                                                                                          IX
                                123/12    Niraj Sagar          Mr. A.K. Sagar      18/06/2007             VIII
                  The commonly used terms of the relational database are:
                      Table: It is a group of related data organised in columns and rows in a database. The columns
                     contain a number of headings such as Reg No., Name, Father's Name, Date of Birth, Class, etc.
                     These are known as fields. A set of values for the fields is called a Record. Each row in the
                     table represents one record.

                      Primary Key: It is a unique field by which the records are uniquely identified in a table. A
                     table can have only one primary key. It ensures that no two records have the same value for
                     this field. For example, in a student’s record the ‘Reg No.’ can be called a primary key.
                      Query: A query is the most powerful feature of database. It allows you to retrieve information

                     from a table based on some criteria or condition. By creating and running a query, you can
                     search, filter, and extract data from the database efficiently.

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