ALTER TABLE table_name
ADD column_name data_type constraint;
-- ALTER TABLE <table> ADD <column> <type> <constraint>;
ALTER TABLE members ADD age NUMBER;
ALTER TABLE members ADD birth_date DATE NOT NULL;
ALTER TABLE members ADD registering DATE DEFAULT sysdate;
ALTER TABLE members ADD member_id NUMBER UNIQUE;
ALTER TABLE table_name
ADD column_name data_type constraint;
SELECT ename, deptno, sal, job FROM emp;