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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)

                 Data Definition Language or Data Description Language  (DDL) is a language that defines 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)

                 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)

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

                 Transaction Control Language (TCL)

                 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 the 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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