linq联合查询后排除相同项.解决方案

linq联合查询后排除相同项.


如上2张表
现在想要的是查询的时候用
主表的字段 CreatorId，IsCompleted，Remarks，CreateDate和子表字段MovieId
做查询条件
查询后将主表字段中相同的排除，

SQL code

select DISTINCT VOD_VodOrder.* from VOD_VodOrder join VOD_VodOrderItem on VOD_VodOrder.Id = VOD_VodOrderItem.ParentId where .....

上面语句能实现，但是用linq怎么做

[解决办法]
查询出来是什么是根据你SELECT后面的东西决定的。
比如你可以
(from t1 in VodOrders join t2 in VodItems on t1.Id equals t2.ParentId select t1).Distinct(); /Distinct(IEqualityComparer<T>);


[解决办法]
linq也有distinct，也有group。
[解决办法]

C# code

var dd=from t1 in VodOrders join t2 in VodItems on t1.Id equals t2.ParentId where...select ... ;dd = dd.Distinct();
[解决办法]
给你一个参考吧
           var varQnum = from pRow in dttRuleData.AsEnumerable()
                         where pRow.Field<string>("NODE_TYPE") == GetLinqQuery(FlowRule.C_TYPE_N)
                         group pRow by pRow.Field<string>("NODE_VALUE")
                             into g
                             select new
                            {
                                g.Key,
                                nodeCode = g.Count()
                            };
[解决办法]
var result =  r1 from vod_vodorder
                 join r2 from vod_vodorderitem  on r1.id eauals r2.id
                where r1.fileld<string >("creatorid") = 变量 &&
r1.fileld<int>("iscompleted") = 变量 &&  
r1.fileld<string>("remarks") = 变量 &&  
r2.fileld<int>("moveid") = 变量  
select new  
{
id = r1.files<string>("id"),
creatorid = r1.fileld<int>("creatorid") ,
iscompleted =r1.fileld<int>("iscompleted"),
remarks = r1.fileld<int>("remarks"),
createdate = r1.fileld<datetime>("createdate")
}.distince().tolist();
 

 

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