DDL : Create, Drop, Alter, Rename, Modify, Truncate

CREATE

Creates a new database object, e.g. CREATE TABLE users (id NUMBER, name VARCHAR2(50));

DROP

Permanently removes an object and its data, e.g. DROP TABLE users; — this cannot be rolled back in most databases.

ALTER / MODIFY

Changes a table's structure, such as adding a column (ALTER TABLE users ADD email VARCHAR2(100);) or modifying a column's definition (ALTER TABLE users MODIFY name VARCHAR2(100);).

RENAME

Renames a database object, e.g. RENAME users TO app_users;

TRUNCATE

Removes all rows from a table quickly while keeping its structure intact, e.g. TRUNCATE TABLE users; — faster than DELETE but cannot be filtered with a WHERE clause and is typically not easily rolled back.