Data Definition Language (DDL)
It is used to create, alter, or drop data structures in the database.
1. CREATE – to create objects in the database
2. ALTER – alters the structure of the database
3. DROP – delete objects from the database
4. TRUNCATE – remove all records from a table, including all spaces allocated for the records are removed
5. COMMENT – add comments to the data dictionary
6. RENAME – rename an object
Data Manipulation Language (DML)
It is used for managing data within schema objects.
1. SELECT – retrieve data from the a database
2. INSERT – insert data into a table
3. UPDATE – updates existing data within a table
4. DELETE – deletes all records from a table, the space for the records remain
5. MERGE – UPSERT operation (insert or update)
6. CALL – call a PL/SQL or Java subprogram
7. EXPLAIN PLAN – explain access path to data
8. LOCK TABLE – control concurrency
Data Control Language (DCL)
It is used to control access to data stored in a database.
1. GRANT – gives user’s access privileges to database
2. REVOKE – withdraw access privileges given with the GRANT command
3. DENY – prevent a user from receiving a particular permission
Transaction Control (TCL)
It is used to manage the changes made by DML statements. It allows statements to be grouped together into logical transactions.
1. COMMIT – save work done
2. SAVEPOINT – identify a point in a transaction to which you can later roll back
3. ROLLBACK – restore database to original since the last COMMIT
4. SET TRANSACTION – Change transaction options like isolation level and what rollback segment to use