Types
- DDL – Data Definition Language
- DQL – Data Query Language
- DML – Data Manipulation Language
- DCL – Data Control Language
- TCL – Transaction Control Language
DDL
- CREATE — create database, create table, create view, create index
- DROP - deletes database, table
- ALTER - change table
- TRUNCATE - removes only the data from table, but not table itself
- RENAME - rename table name
DQL
- SELECT — used to retrieve data from the database.
DML
List of DML commands:
- INSERT : It is used to insert data into a table.
- UPDATE: It is used to update existing data within a table.
- DELETE : It is used to delete records from a database table.
- LOCK: Table control concurrency.
TCL
A transaction is a single unit of work. If a transaction is successful, all of the data modifications made during the transaction are committed and become a permanent part of the database. If a transaction encounters errors and must be canceled or rolled back, then all of the data modifications are erased.
- COMMIT: Commits a Transaction.
- ROLLBACK: Rollbacks a transaction in case of any error occurs.
- SAVEPOINT: Sets a savepoint within a transaction.
- SET TRANSACTION: Specify characteristics for the transaction.
