Here are some examples of Oracle alter table syntax to modify data columns and note that you can add constraints like NOT NULL: ALTER TABLE customer MODIFY (cust_name varchar2(100) not null, cust_hair_color varchar2(20)) ;
Did Sir Isaac Newton write any books? His best known book is Principia (Philosophiae Naturalis Principia Mathematica) published in 1687; which includes his laws of motion. Edit
Another Isaac Newton invention is what is known as the Calculus (another mathematician known at Gottfried Leibniz also worked on the calculus during this time). The calculus is a complex mathematical theoretical system that is today used in abstract mathematics, astronomy, geometry, financial mathematics and statistics.