1.
select a.intid as ID ,a.Strname as 姓名,b.Strcaption as 学历 ,c.Strcaption as 民族
from person a, BaseCode b,BaseCode c
where a.Inteducationid=b.intid and a.Intnationid=c.intid
select a.intid as ID ,a.Strname as 姓名,b.Strcaption as 学历 ,c.Strcaption as 民族
from person a, BaseCode b,BaseCode c
where a.Inteducationid=b.intid and a.Intnationid=c.intid
insert into student values('张三' , '语文' , 85 )
insert into student values('李四', '语文' , 80 )
insert into student values('张三' , '英语' , 85 )
select 姓名,语文=(sum(case 学科 when '语文' then 成绩 else 0 end )) ,英语=(sum(case 学科 when '英语' then 成绩 else 0 end )),数学=(sum(case 学科 when '数学' then 成绩 else 0 end ))
from student
group by 姓名
如果:张三的学历为未知也就是
表person中Inteducationid为空或不在表BaseCode字段Intid中
那就查不出这个结果
而要求为插入未知