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#INTRODUCTION


                                                        TO MYSQL










        MySQL is an open-source RDBMS software which is available free of cost.  It can run on all
        operating  systems, including  Linux,  Unix  and  Windows.  It  is popular  for web-based  applications
        and  online  publishing.  It uses a query  language  called  SQL  (Structured Query  Language).
        SQL is the standard language for managing relational databases and performing various operations on
        the data in the tables. It is used to store, retrieve, and manipulate data in the form of tables.

        TYPES OF SQL COMMANDS


        SQL uses various commands to perform different operations on a database.
        Data Definition Language (DDL)

        A Data Definition Language or Data Description Language  (DDL) is a standard for commands that
        define the different structures in a database. DDL statements create, modify and remove database
        objects such as tables, indexes and users. Common DDL statements are CREATE, ALTER, TRUNCATE,
        RENAME and DROP.

        Data Manipulation Language (DML)

        A Data Manipulation language (DML) is a language that enables users to retrieve, update, insert and
        delete data in a database. Common DML statements are SELECT, UPDATE, INSERT INTO and DELETE.

        Data Control Language (DCL)

        A Data Control Language is a language that has various commands which are used to grant and take
        back authority from any database user. Some DCL statements are Grant and Revoke.

        Transaction Control Language (TCL)

        A Transaction Control Language is a language that has various commands which are used to manage
        transactions in the database. These are used to manage the changes made by DML-statements. Some
        TCL statements are Commit, Savepoint and Rollback.

        DATA TYPES IN SQL


        A data type defines a sort of value that a column will contain. In a database table, every column must
        have a name and data type.










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