text: DROP TABLE IF EXISTS author_ISBN;
  DROP TABLE IF EXISTS titles;
  DROP TABLE IF EXISTS authors;
  
  CREATE TABLE authors (
      id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
      first TEXT NOT NULL,
      last TEXT NOT NULL
  );
  
  CREATE TABLE titles (
      isbn TEXT NOT NULL,
      title TEXT NOT NULL,
      edition INTEGER NOT NULL,
      copyright TEXT NOT NULL,
      PRIMARY KEY (isbn)
  );
  
  CREATE TABLE author_ISBN (
      id INTEGER NOT NULL,
      isbn TEXT NOT NULL,
      PRIMARY KEY (id, isbn),
      FOREIGN KEY (id) REFERENCES authors(id) ON DELETE CASCADE, 
      FOREIGN KEY (isbn) REFERENCES titles (isbn) ON DELETE CASCADE
  );
  
  PRAGMA foreign_keys = ON;
  
  INSERT INTO authors (first, last)
  VALUES 
      ('Paul','Deitel'), 
      ('Harvey','Deitel'),
      ('Abbey','Deitel'), 
      ('Dan','Quirk'),
      ('Alexander', 'Wald');
  
  INSERT INTO titles (isbn,title,edition,copyright)
  VALUES
      ('0135404673','Intro to Python for CS and DS',1,'2020'),
      ('0132151006','Internet & WWW How to Program',5,'2012'),
      ('0134743350','Java How to Program',11,'2018'),
      ('0133976890','C How to Program',8,'2016'), 
      ('0133406954','Visual Basic 2012 How to Program',6,'2014'),
      ('0134601548','Visual C# How to Program',6,'2017'),
      ('0136151574','Visual C++ How to Program',2,'2008'),
      ('0134448235','C++ How to Program',10,'2017'),
      ('0134444302','Android How to Program',3,'2017'),
      ('0134289366','Android 6 for Programmers',3,'2016');
  
  INSERT INTO author_ISBN (id,isbn)
  VALUES
      (1,'0134289366'),
      (2,'0134289366'),
      (5,'0134289366'),
      (1,'0135404673'),
      (2,'0135404673'),
      (1,'0132151006'),
      (2,'0132151006'),
      (3,'0132151006'),
      (1,'0134743350'),
      (2,'0134743350'),
      (1,'0133976890'),
      (2,'0133976890'),
      (1,'0133406954'),
      (2,'0133406954'),
      (3,'0133406954'),
      (1,'0134601548'),
      (2,'0134601548'),
      (1,'0136151574'),
      (2,'0136151574'),
      (4,'0136151574'),
      (1,'0134448235'),
      (2,'0134448235'),
      (1,'0134444302'),
      (2,'0134444302');
  