There are number of SQL Commands in SQl Server and we categorize these commands into subgroups.
These subgroups are:
· Data Definition Language (DDL)
· Data Manipulation Language (DML)
· Data Control Language (DCL)
Data Definition Language: DDL deals with database schemas and descriptions of how the data should reside in the database, therefore language statements like CREATE TABLE or ALTER TABLE belong to DDL.
Data Manipulation Language: DML deals with data manipulation, and therefore includes most common SQL statements such SELECT, INSERT, etc.
Data Control Language: DCL includes commands such as GRANT, and mostly concerns with rights, permissions and other controls of the database system.