如何用c#linq中另一个查询的结果减去一个查询的结果？
我想从如何用c#linq中另一个查询的结果减去一个查询的结果？,c#,linq,C#,Linq,我想从investment中获取记录，并从investment\u Line中计算金额的总和，其中investment\u Line.ParentID==investment.investment 减去金额Calculte==d.Amount-Answer var a = (from investment in _entities.Investments where investment.StatusID == 4 select new {
investmentinvestment\u Line金额的总和，其中investment\u Line.ParentID==investment.investment
减去金额Calculte==d.Amount-Answer
var a = (from investment in _entities.Investments
where investment.StatusID == 4
select new
{
RefNo = investment.RefNo,
InvestedAmount = investment.InvestedAmount,
Amount = investment.InvestedAmount + investment.ProfitAmount,
InvestmentID = investment.ID,
UserID = investment.UserID,
StatusID = investment.StatusID,
}).ToList();
if (a.Count() != 0)
{
foreach (var row in a)
{
var count = (_entities.Investment_Line.Where(x => x.ParentID == row.InvestmentID)).Count();
if(count != 0)
{
var _group = _entities.Investment_Line.Where(x => x.ParentID == row.InvestmentID).GroupBy(g => g.ParentID).Select(s => new { SumAmount = s.Sum(sum => sum.Amount) });
double answer = double.ConvertToDouble(_group.Select(x => x.SumAmount));
var data = (from d in a
select new Search.ReadyInvestmentList
{
RefNo = d.RefNo,
InvestedAmount = d.InvestedAmount,
TotalAmount = d.Amount,
InvestmentID = d.InvestmentID,
UserID = d.UserID,
StatusID = d.StatusID,
Calculate = d.Amount-answer
}).ToList();
}
}
}
投资表
+---+--------------------------+--------+-------------+----------------+--------+-------------+----------+
|ID | CreateDate | UserID | RefNo | InvestedAmount | Growth%| ProfitAmount|StatusID |
+---+--------------------------+--------+-------------+----------------+--------+-------------+----------+
|1 | 2017-01-11 16:39:06.483 | 1 | BPWM57G2Q2 | 20000 | 30 | 6000 | 4 |
|2 | 2017-01-11 16:49:18.850 | 2 | BPWM56H2T0 | 10000 | 30 | 3000 | 4 |
|3 | 2017-01-11 17:15:02.667 | 3 | BPWM56G2L0 | 500 | 30 | 1500 | 1 |
|4 | 2017-01-12 20:22:02.160 | 5 | BPWM68L2I0 | 500 | 30 | 150 | 2 |
|5 | 2017-01-12 20:25:03.160 | 5 | BPWM63F2I5 | 2000 | 30 | 600 | 4 |
+---+--------------------------+--------+-------------+----------------+--------+-------------+----------+
+----+-------------+-----------+-----------+-------+------------+-----------+
| ID | InvestmentID| InvestorID| AssistorID| Amount| RefNo | ParentID |
+----+-------------+-----------+-----------+-------+------------+-----------+
| 1 | 2 | 2 | 1 | 10000 | BPWM56H2T0 | 1 |
| 2 | 3 | 3 | 1 | 5000 | BPWM56G2L0 | 1 |
| 3 | 4 | 5 | 3 | 500 | BPWM68L2I0 | 3 |
+----+-------------+-----------+-----------+-------+------------+-----------+
投资行表
+---+--------------------------+--------+-------------+----------------+--------+-------------+----------+
|ID | CreateDate | UserID | RefNo | InvestedAmount | Growth%| ProfitAmount|StatusID |
+---+--------------------------+--------+-------------+----------------+--------+-------------+----------+
|1 | 2017-01-11 16:39:06.483 | 1 | BPWM57G2Q2 | 20000 | 30 | 6000 | 4 |
|2 | 2017-01-11 16:49:18.850 | 2 | BPWM56H2T0 | 10000 | 30 | 3000 | 4 |
|3 | 2017-01-11 17:15:02.667 | 3 | BPWM56G2L0 | 500 | 30 | 1500 | 1 |
|4 | 2017-01-12 20:22:02.160 | 5 | BPWM68L2I0 | 500 | 30 | 150 | 2 |
|5 | 2017-01-12 20:25:03.160 | 5 | BPWM63F2I5 | 2000 | 30 | 600 | 4 |
+---+--------------------------+--------+-------------+----------------+--------+-------------+----------+
+----+-------------+-----------+-----------+-------+------------+-----------+
| ID | InvestmentID| InvestorID| AssistorID| Amount| RefNo | ParentID |
+----+-------------+-----------+-----------+-------+------------+-----------+
| 1 | 2 | 2 | 1 | 10000 | BPWM56H2T0 | 1 |
| 2 | 3 | 3 | 1 | 5000 | BPWM56G2L0 | 1 |
| 3 | 4 | 5 | 3 | 500 | BPWM68L2I0 | 3 |
+----+-------------+-----------+-----------+-------+------------+-----------+
所需输出
+----+---------+-----------+-------+---------------+------------+-----------+
| InvestmentID | RefNo | UserID| InvestedAmount| TotalAmount| Calculate |
+--------------+--------------------+--------------+------------+-----------+
| 1 | BPWM57G2Q2| 1 | 20000 | 26000 | 15000 |
| 2 | BPWM56H2T0| 2 | 10000 | 13000 | 0 |
| 5 | BPWM63F2I5| 5 | 2000 | 2600 | 0 |
+----+---------+-----------+-------+-------------- +------------+-----------+
最好的方法是什么？
请提供帮助。如果主详细信息表中有许多记录，则代码的性能将很差。因为您将有masterRecordCount*DetailRecordCount
嵌套循环。因此，如果您分组并加入一个查询，效果会更好
var calculatedlist = from I in _entities.Investments
join IL in _entities.Investment_Line on I.ID equals IL.ParentID
group IL by new { I.ID } into g
select new {
InvestmentID = g.Key,
RefNo = g.Max(m => m.I.RefNo),
UserID = g.Max(m => m.I.UserID) ,
InvestedAmount = g.Max(m => m.I.InvestedAmount) ,
TotalAmount = g.Max(m => m.I.InvestedAmount) + g.Max(m => m.I.ProfitAmount),
Calculate = g.Max(m => m.I.InvestedAmount) + g.Max(m => m.I.ProfitAmount) - g.Sum(m => m.IL.Amount)
};
若主详细信息表中有许多记录，则代码的性能将很差。因为您将有masterRecordCount*DetailRecordCount
嵌套循环。因此，如果您分组并加入一个查询，效果会更好
var calculatedlist = from I in _entities.Investments
join IL in _entities.Investment_Line on I.ID equals IL.ParentID
group IL by new { I.ID } into g
select new {
InvestmentID = g.Key,
RefNo = g.Max(m => m.I.RefNo),
UserID = g.Max(m => m.I.UserID) ,
InvestedAmount = g.Max(m => m.I.InvestedAmount) ,
TotalAmount = g.Max(m => m.I.InvestedAmount) + g.Max(m => m.I.ProfitAmount),
Calculate = g.Max(m => m.I.InvestedAmount) + g.Max(m => m.I.ProfitAmount) - g.Sum(m => m.IL.Amount)
};
您在LINQ查询中引用的一些列名以及您的问题似乎与您提供的示例表的列名不匹配，或者缺少，例如ActiveYN。@MattD我已更新了我的问题您在LINQ查询中引用的一些列名，以及您的问题似乎与您提供的示例表的列名不匹配，或者缺少，例如ActiveYN。@MattD我已更新了我的问题