问题描述
让我们说我有2个表,它们都包含动态列,我希望在执行左外部联接后从两个表中检索所有列的数据行集合(以后我将其绑定到网格视图).
Lets say I have 2 tables both of them contain dynamic columns and I wish to retrieve a collection of datarow with all the columns from both the tables(later i will bind it to a grid view) after performing left outer join.
样本查询:
var query = from TableA in ds.Tables[0].AsEnumerable()
join TableB in ds.Tables[1].AsEnumerable() on new { col1 = TableA.Field<Int32>("colA"), col2 = TableA.Field<DateTime>("colB") }
equals new { col1 = TableB.Field<Int32>("colA"), col2 = TableB.Field<DateTime>("colB") }
into GJ
from sub in GJ.DefaultIfEmpty()
select TableA;
问题:我想一起选择tableA和tableB.上面的示例查询有效,并且在左外部联接之后填充了tableA的所有列.但是我希望从两个表中检索所有列.请指教.
Problem:I want to select tableA and tableB together. The above sample query works and it populates all columns of tableA after left outer join. But i wish to retrieve all the columns from both the tables. Please advice.
推荐答案
只需将两个部分都选择为匿名类型:
Just select both parts into an anonymous type:
var query = from TableA in ds.Tables[0].AsEnumerable()
join TableB in [ ...] on [...] equals [...] into GJ
from sub in GJ.DefaultIfEmpty()
select new { RowA = TableA, RowB = sub };
结果的每个元素将具有两个属性:RowA
是TableA
的行,RowB
是TableB
的匹配行;如果TableB
匹配RowA
.
Each element of the result will have two properties: RowA
being a row from TableA
, and RowB
being a matching row from TableB
or null if no rows from TableB
matches RowA
.
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