12两本书.sql

1.写出建立BORROW表的SQL语句

SELECT X.CNO FROM BORROW AS X, BORROW AS Y  
   WHERE  X.CNO=Y.CNO AND X.BNO IN
     (SELECT BORROW.BNO FROM BOOKS,BORROW
      WHERE BOOKS.BNO=BORROW.BNO AND BNAME='计算方法')AND Y.BNO IN 
     (SELECT BORROW.BNO FROM BOOKS,BORROW
      WHERE BOOKS.BNO=BORROW.BNO AND BNAME='组合数学')
 ORDER BY Y.CNO