A.select staffno from staff where E_mail=NULL B.select staffno from staff where E_mail NULL C.select staffno from staff where E_mail is NULL D.select staffno from staff where E_mail is not NULL
A.SELECT price FROM book WHERE book_name=“數據庫*” B.SELECT price FROM book WHERE book_name LIKE“數據庫*” C.SELECT price FROM book WHERE book_name=“數據庫%” D.SELECT price FROM book WHERE book_name LIKE“數據庫%”
A.DROP SCHEMA B.CREATE TABLE C.DROP VIEW D.DROP INDEX