Linq to Sql select from multiple table
I have a question about selecting from multiple tables in C# using Linq.
Table structure is like this:
TABLE A
TableAID Column1 Column2TABLE B
TableBID TableAID Column3 Column4So in code i have:
List<string> myList = new List{"Test1","Test2"};
var myView = MYDC.TableA.AsQueryAble();
If I want to select records from table A using where on Column1, I would simply use:
myView = myView.Where(k=>myList.Contains(k.Column1));
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But if I want to preserve the myView as queryable of TableA and if I want to use where on TableB on Column3, which is linked to TableA with a foreign key, how would I do it?
I tried the following with no success:
myView = myView.Where(k=>myList.Contains(k.TableB.Select(kk=>kk.Column3)));
Any suggestions?
Thanks in advance
There are several ways to to this. Here are two of them:
var q = (
from b in MYDB.TableB
where myList.Contains(b.Column3)
select b.TableA).Distinct();
var q =
from a in myView
let bs = a.TableB.Where(b => myList.Contains(b.Column3))
where bs.Any()
select a;
I hope this helps.
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