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3. UPDATE statement: To modify or change the data (tuple) in a table (not modifying the data
type of column).

4. DELETE: To delete data (tuple) from a table (not deleting a column).

Table 12.1 Difference between DDL and DML commands
DDL Commands DML Commands
1. DDL stands for Data Definition Language. 1. DML stands for Data Manipulation Language.
2. These commands allow us to perform tasks related 2. These commands are used to manipulate data, i.e.,
to data definition, i.e., related to the structure of the records or rows in a table or relation.
database objects (relations/databases).
3. The examples of DDL commands are Create, Alter, 3. The examples of DML commands are Insert into,
Drop, Grant, Revoke, etc. Update, Delete, Select, etc.
4. DDL is not further classified. 4. DML commands are further classified into two types:
(a) Procedural DMLs
(b) Non-Procedural DMLs

Let us start implementing SQL using MySQL as the platform.

12.11 MYSQL

MySQL is an open-source and freely available Relational Database Management System (RDBMS)
that uses Structured Query Language (SQL). It provides excellent features for creating, storing,
maintaining and accessing data, stored in the form of databases and their respective tables. A
single MySQL database can store several tables at a time and can store thousands of records in it.

Being an open-source software, it can be freely and easily downloaded from the site
www.mysql.org. MySQL is developed and supported by a Sweden-based company, MySQL AB. It is
fully secured, reliable, and fast, and possesses far better functionalities than many other commercial
RDBMs available in the market.
MySQL database system works upon Client/Server architecture. It constitutes a MySQL server
which runs on a machine containing the databases and MySQL databases (clients), which are
connected to these server machines over a network.

F Advantages of MySQL: MySQL provides the following salient features and advantages:
1. Reliability and Performance: MySQL is a very reliable and high performance Relational
Database Management System.
2. Modifiable: Being an open-source software, MySQL comes with its source code; so, it is
easily modifiable and we can recompile its associated source code.
3. Multi-Platform Support: MySQL supports several different platforms like UNIX, Linux,
Mac OS X and Microsoft Windows.

4. Powerful Processing Capabilities: MySQL is a powerful, easy, compatible and
Relational Database and SQL
fast Relational Database Management System. It can handle complicated corporate
applications and processing requirements.
5. Integrity (Checks): MySQL provides various integrity checks in order to restrict the user
input and processing.
6. Authorization: MySQL provides DDL commands to check for user authentication and
authorization by restricting access to relations and views.

12.15