DDL DML DCL TCL
DDL is abbreviation of data Definition Language. it’s used to create and modify the structure of database objects in database.
SELECT – retrieve data from the a database
INSERT – insert data into a table
UPDATE – updates existing data within a table
DELETE – deletes all records from a table, the space for the records remain
MERGE – UPSERT operation (insert or update)
CALL – call a PL/SQL or Java subprogram
EXPLAIN PLAN – explain access path to data
LOCK TABLE – control concurrency
DML is abbreviation of data Manipulation Language. it’s used to retrieve, store, modify, delete, insert and update information in database.
CREATE – to create objects in the database
ALTER – alters the structure of the 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
DCL is abbreviation of data control Language. it’s used to create roles, permissions, and referential integrity similarly it’s used to control access to database by securing it.
GRANT – gives user’s access privileges to database
REVOKE – withdraw access privileges given with the GRANT command
TCL is abbreviation of Transactional control Language. it’s used to manage completely different transactions occurring inside a database.
COMMIT – save work done
SAVEPOINT – identify a point in a transaction to which you can later roll back
ROLLBACK – restore database to original since the last COMMIT
SET TRANSACTION – Change transaction options like isolation level and what rollback segment to use