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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 a language that is used 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. These SQL commands are used to interact with the data stored in a relational
              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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