createtable student (
id int,
name varchar(20),
age int,
sex varchar(5),
address varchar(100),
math int,
english int);insertinto student
(id,name,age,sex,address,math,english)values(1,'马云',55,'男','杭州',66,78),(2,'马化腾',45,'女','深圳',98,87),(3,'马景涛',55,'男','香港',56,77),(4,'柳岩',20,'女','湖南',76,65),(5,'柳青',20,'男','湖南',86,NULL),(6,'刘德华',57,'男','香港',99,99),(7,'玛德',22,'女','香港',99,99),(8,'德玛西亚',18,'男','南京',56,65);