DDL
DDL is short name of Data Definition Language,which deals with database schemas and descriptions, of how the data should reside in the database.
CREATE– to create database and its objects like (table, index, views, store procedure, function and triggers)
ALTER – alters the structure of the existing database
DROP – delete objects from the database
TRUNCATE – remove all records from a table, including all spaces allocated for the records are removed
COMMENT – add comments to the data dictionary
RENAME – rename an object
DML
DML is short name of Data Manipulation Languagewhich deals with data manipulation, and includes most common SQL statements such SELECT, INSERT, UPDATE, DELETE etc, and it is used to store, modify, retrieve, delete and update data in database.
SELECT– retrieve data from the a database
INSERT– insert data into a table
UPDATE– updates existing data within a table
DELETE– Delete all records from a database table
MERGE – UPSERT operation (insert or update)
CALL – call a PL/SQL or Java subprogram
EXPLAIN PLAN – interpretation of the data access path
LOCK TABLE – concurrency Control
DCL
DCL is short name of Data Control Languagewhich includes commands such as GRANT, and mostly concerned with rights, permissions and other controls of the database system.
GRANT – allow users access privileges to database
REVOKE – withdraw users access privileges given by using the GRANT command
TCL
TCL is short name of Transaction Control Language which deals with transaction within a database.
COMMIT – commits a Transaction
ROLLBACK – rollback a transaction in case of any error occurs
SAVEPOINT – to rollback the transaction making points within groups
SET TRANSACTION – specify characteristics for the transaction
