数据库 SQL练习3

SELECT: 【例3.29】 SELECT * FROM Student WHERE Sno LIKE '201215121'; 等价于(注意‘’里别多填了空格) SELECT * FROM Student WHERE Sno='201215121'; 如果后面的匹配串中不含通配符,则可以用=运算符取代LIKE,用!=或(不等于)运算符取代NOT LIKE。 SELECT * FROM Student WHERE Sno NOT LIKE '201215121'; /*等价于*/ SELECT * FROM Student WHERE Sno'201215121'; /*等价于*/ SELE