SQL commands classification

SQL commands can be classified into four groups :-

• DDL - Data Definition Language :
• CREATE - Creates new table, view of tables and other objects in database
• ALTER - Used to modify or change an existing  database objects such as tables.
• DROP - Used to  delete tables or views or other object in the database.

• DML - Data Manipulation Language :
•  INSERT - Create a new record in a table.
• UPDATE - Modifies records in a table.
• DELETE - Deletes records in a table.

•  DCL - Data Control Language:
• GRANT - Give a privilege to user.
• REVOKE - Revokes  the privileges granted to a user.

• DQL- Data Query Language
• SELECT - Retrieves certain records from one or more tables.