SQL refresh

DDL - Data Defination Language ( CREAT,ALTER, DROP,RENAME)
DML -Date Munipulation Language (SELECT, INSERT,UPDATE,DELETE)
TCL - Transaction Control Language
DCL - Data Control Language

CREATE TABLE employee ( id number(5), name char(20),dept char(10),age number(2), salary number(10) );

ALTER TABLE employee MODIFY salary number(10,2);
ALTER TABLE employee ADD phone number(10);
ALTER TABLE employee DROP age;

RENAME employee to my_employee

SELECT name FROM employee
WHERE age>35
GROUP BY dept
ORDER BY id