select a.classid,a.className,a.classTeacher,sum(b.maths) as maths,sum(b.chinese) as chinese
from a,b
where a.classid=b.classid
group by a.classid,a.className,a.classTeacher
from a,b
where a.classid=b.classid
group by a.classid,a.className,a.classTeacher
如果在sql里可以对nText做Group by 操作
from a,(select classid,sum(b.maths) as maths,sum(b.chinese) as chinese
from b group by classid) as c
where a.classid=c.classid
B表 有 stuId,classid,studentName,studentSex,maths,chinese,等字段,一个班有多个学生,现在我要生成这样一张表,按班排,所有相同班不同学生的成绩maths和chinese全部相加起来!!
比如,A表有五个班,那么最后得到的是五条记录,并且统计出每个班的总成绩。谢谢。select A.className,sum(B.maths),sum(B.chinese) from B inner join A on B.classid=A.classid group by A.className