Languages in SQL
Languages in SQL
SQL itself is a language for managing and manipulating relational databases, but within SQL, you often work with different sub-languages or categories of commands. These categories define different types of operations you can perform.
The Main SQL Sub-languages:
1. DDL (Data Definition Language)
Used to define or modify database structure (tables, schemas, indexes).
Commands:
CREATE,ALTER,DROP,TRUNCATE,RENAME
2. DML (Data Manipulation Language)
Used to manage data inside tables.
Commands:
INSERT,UPDATE,DELETE,MERGE
3. DCL (Data Control Language)
Used to control access and permissions on database objects.
Commands:
GRANT,REVOKE
4. TCL (Transaction Control Language)
Used to manage transactions (groups of SQL statements).
Commands:
COMMIT,ROLLBACK,SAVEPOINT,SET TRANSACTION
5. DQL (Data Query Language)
Used to query or retrieve data.
Command:
SELECT
Summary Table
| Sub-language | Purpose | Example Commands |
|---|---|---|
| DDL | Define or modify database schema | CREATE, ALTER, DROP |
| DML | Manipulate data | INSERT, UPDATE, DELETE |
| DCL | Manage permissions | GRANT, REVOKE |
| TCL | Control transactions | COMMIT, ROLLBACK |
| DQL | Query data | SELECT |
If you want, I can explain any of these languages or their commands in more detail!
