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•  All the users are provided with some access rights, privileges, and permissions.

                 •  The files can be easily updated whenever any changes are made.

                  i +  TYPES OF DATABASES

                 There are mainly two types of databases:
                 •  Flat File Database: It is a type of database that contains records having a small
                    number of fields without any structured relationship between them. The most
                    popular example of a flat file database is Excel 2016.                                  Excel 2016
                 •  Relational Database: It is a type of database that stores
                    data in several tables and links those tables together to
                    get  a  common piece of information.  Commonly used
                    relational database systems are Microsoft Access, Microsoft SQL Server, ORACLE, etc.
                    Info Byte


                     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.


                  i +  TERMS RELATED TO A DATABASE

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

                                                               FIELDS


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


                              194/11
                                         Suraj Patel
                                                                                 16/04/2008
                                                                                                         IX
                                                             Mr. G.S. Patel
                              123/12     Priyansh Sagar      Mr. P.K. Sagar      18/06/2007             VIII
                 The commonly used terms in a 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. A record is
                    one row of the table.
                 •  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. For example, in a student’s record, the ‘Reg No.’ can be
                    called a primary key.

                 •  Query: A query is the most powerful object in a database. It helps you retrieve information
                    from a table based on some criteria or conditions. You can find, and retrieve data from the
                    database just by creating and running the query.

                 •  Report: The final result of the manipulated data that comes from tables or queries in a DBMS
                    is known as a report. A report is a database object that is specially designed to display or print
                    the data in a formatted way.




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                                                                            Database and DBMS—An Introduction
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