例如:
grade class id name english math chinese
1 501 50101 dsfe 80 90 40
2 501 50101 dsfe 80 70 60

能不能先设置primary key,会简单一些.

不能设``因为我要用VC对它操作的`
如果设的话``一些重复就不行了``
我只要实现该功能的SQL语句

if not exists(select * from aaa where aa='a' and bb='b' and cc='c' )
insert into aaa values('a','b','c')

这是我在数据库的定义
grade int 4 0
class char 50 0
id char 50 0
name char 50 0
english float 8 0
math float 8 0
chinese float 8 0
summark float 8 1(允许为空)
average float 8 1(允许为空)

执行语句:
IF NOT EXISTS (SELECT *
FROM student
WHERE grade = 1 AND class = '503' AND id = '50333' AND
name = 'kkkk' AND english = 60 AND math = 70 AND chinese = 80)
INSERT
INTO student
VALUES (1, '503', '50333', 'kkkk', 60, 70, 80)

出错:查询计算器不支持IF SQL构造
出错:插入出错:列名或所提供值的数目与表定义不匹配

你插入的VALUES (1, '503', '50333', 'kkkk', 60, 70, 80)中缺少summark和average的数值。

``谢谢``