Chapter 3, Problem 3.1RQ

Explanation of Solution

SQL:

• The full form of SQL is “Structured Query Language”.
• SQL is not a programming language. It is text-based and it is also called as data sublanguage.
  • In order to get SQL as a complete programming language, it should be included in scripting languages like Java, C#, and so on.
• Some of the DBMS (Database Management System) products provide GUI (Graphical User Interface) tools in order to perform tasks are as follows:
  • SQL Server
  • Oracle Database
  • MySQL

Importance of SQL:

• SQL language is used to work with database like defining and processing it. They are executed using DBMS-supplied command prompt.
• They can control redundant data and also it can restrict unauthorized access.

SQL Commands:

SQL statements are divided into categories. Some of them are given below:

• Data Definition Language (DDL):
  • It is used for creating tables and other structures. They perform operations like creating tables, modifying database, and removing database.
• Data Manipulation Language (DML):
  • This is used for manipulation like querying, inserting, updating, and deleting data.
• SQL / Persistent Stored Module (SQL / PSM):
  • These are which extended by including procedural programming capabilities like variables and control statements.
• Transaction Control Language (TCL):
  • These statements are used to control transactions. The commands of TCL are: Commit, Rollback, and Savepoint
• Data Control Language (DCL):
  • They are used to “grant or revoke” permissions for database.