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    The need for databases is as follows:  Amit Sen  Amit Sen  Microsoft Access, Oracle, MySQL, etc. are some of commonly used RDBMS.
     Richa Tondon  Richa Tondon
       Reduction of data  redundancy: It  refers to  unnecessary   Deepak Patel  Deepak Patel  DBMS vs RDBMS
     duplication of data. A centralised database helps avoid this   Nitish Reddy  Nitish Reddy
     Anil Gurang  Anil Gurang                     Table               Table
     by storing only one version of the data.  Amit Sen
     Richa Tondon                                          Table
                       xml                        Table               Table
       Data sharing: It  allows multiple  users  to  access  and     xml
     work on the  same  data  simultaneously,  facilitating     xml  Table       The Relational  Model  was proposed  in
                             xml                                                 1970 by E.F. Codd of IBM.
     real-time collaboration.   xml
                         DBMS                             RDBMS
       Data security: It ensures data safety through security systems, user
     roles and permissions, allowing only authorised users to access and   COMPONENTS OF RELATIONAL DATABASE

     modify the data.
                     The key components of a relational database are as follows:
                                                                Student Table

       Data  integrity: Data  integrity  ensures that data  is  accurate,   Fields
     consistent and reliable. Databases use constraints to prevent errors,   Student_ID  First_Name  Last_Name  Date of Birth  Email  Course_ID
     such as disallowing negative quantities or verifying that a supplier   1  Aarav  Sharma  15-Mar-2012  aarav.sharma@gmail.com  C101
     exists before processing an order.  2  Priya  Patel        20-May-2012   priya.patel@gmail.com     C102
                         Table  3      Rahul       Verma        10-Mar-2012   rahul.verma@gmail.com     C103         Records

                               4       Sneha       Iyer         25-Nov-2011   sneha.iyer@gmail.com      C101
       Data backup: Data backup in databases means making a copy of the   5  Dev  Kapoor  12-Jul-2012  dev.kapoor@gmail.com  C102
     database files so that you can restore your data if it gets lost, damaged
     or corrupted. It is a safety measure to protect important information.  The different components of a relational database are as follows:

                         Tables: A table is a collection of related records arranged in rows and columns. Each column
                        represents a specific type of information (attribute) and each row represents a record (tuple)
     DATABASE MANAGEMENT SYSTEM (DBMS)  containing related data.

     A Database Management System (DBMS) is a software that allows users to control the creation,     Fields: A field represents one related part of a table. It contains the same kind of data in a
     maintenance and use of a database. It performs the tasks of maintaining databases so that the   table. For example, Student_ID, First_Name, Last_Name, Date of Birth, Email and Course_ID

     information is readily available. It helps to manage the data of different fields like banks, offices,   are fields in the table.
     railways, airlines, etc. DBMS allows users to store, manage and organise all the data in a way that     Records: A record is a collection of related data stored in different fields, treated as a single
     makes it easy to find and use whenever they need it.  unit. It represents the data which is entered in a set of different fields which are related to a
                        particular item. For example, 1, Aarav, Sharma, 15-Mar-2012, aarav.sharma@gmail.com and
                        C101 is one of the records of the table.
     RELATIONAL DATABASE MANAGEMENT SYSTEM (RDBMS)
                     KEYS IN DATABASE
     A relational database is a type of database that stores data in the form of tables. These tables are   A key is a column or set of columns that identifies records in a table. It is also called a key field and
     structured with rows and columns and they can be related to each other through common fields   can link data between tables. The most common types of keys in SQL are the primary key and the
     (keys) to enable the retrieval of related information. The software package that is used to handle   foreign key.
     relational databases is known as the Relational Database Management System (RDBMS).

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                                                                                              MySQL: My First Database

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