SQL Commands are mainly classified into four types, which are DDL command, DML command, TCL command and DCL command.
SQL is mainly divided into four sub language
1. Data Definition Language (DDL)
Data Definition Language (DDL) is a standard for commands that define the different structures in a database. DDL statements create, modify, and remove database objects such as tables, indexes, and users.
2. Data Manipulation Language (DML)
A data manipulation language (DML) is a family of syntax elements similar to a computer programming language used for selecting, inserting, deleting and updating data in a database.
3. Transaction Control Language (TCL)
Transaction Control Language (TCL) used to control transactional processing in a database. A transaction is logical unit of work that comprises one or more SQL statements, usually a group of Data Manipulation Language (DML) statements.
4. Data Control Language (DCL)
The Data Control Language (DCL) component of the SQL language is used to create privileges to allow users access to, and manipulation of, the database.
•DDL Commands “dr. cat” d-drop, r-remane, c-create, a-alter, t-truncate.
•DML commands “sudi”. s-select, u-update, d-delete, i-insert.