Different Types of SQL Commands
SQL commands can be classified into the following three types:
1. Data Definition Language
2. Data Manipulation Language
3. Data Control Language
Data Definition Language:
It is a part of SQL which consists of those commands that create the objects (tables, indexes, views, etc.) in the databases. Create, Drop and Alter are a few commands of DDL language.
Data Manipulation Language:
It is part of SQL which consists of a set of commands that determine which values are present in the tables at any given time.
Data Manipulation Language is divided into three categories:
Data Control Language:
It is another portion of SQL which allows the definition of a security mechanism or schema for protecting data from unauthorized access. DCL consists of features that determine whether a user is permitted to perform a particular action. It contains commands like GRANT, REVOKE, etc. These are also known as Transaction Control Commands.