我有两个db.Table1和db.Table2,列名为IdUser,Value 我想我应该有一些加入,但我错过了逻辑
这只是一个逻辑,它不是代码 怎么能做:
var total = Sum(db.Table1(Sum(Value))-db.Table2(Sum(Value))
.Where(db.Table1.IdUser=db.Table2.IdUser)
答案 0 :(得分:1)
加入表格和小组
var total = from table1record in Table1
join table2record in Table2 on table1Record.IdUser equals table2Record.IdUser
group new { table1record,table2record } by table1record.IdUser into groupedRecords
select groupedRecords.Sum(x=>x.Table1Value) - groupedRecords.Sum(x=>x.Table2Value);