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
Isaac Newton's Papers and Letters on Natural Philosophy, 2nd ed., ed. I. B. Cohen and R. E. Schofield, Cambridge: Harvard University Press, 1978. Contains all the papers on optics published in the early 1670s, the letters to Bentley, and Fontenelle's Elogium, among other things).