Linq- left join on dbset












0















I have 2 tables:



A {

    IDA

    propA1

    propA2

}

B {

    IDA,

    IDB,

    propB1,

    propB2

}


I want to get all records from table A such that IDA is not contained in table B where IDB = "someValue".
The query is using linq.






linq







share|improve this question




















  • 1





    so you don't want a left join...

    – Florian
    Nov 26 '18 at 8:44
















0















I have 2 tables:



A {

    IDA

    propA1

    propA2

}

B {

    IDA,

    IDB,

    propB1,

    propB2

}


I want to get all records from table A such that IDA is not contained in table B where IDB = "someValue".
The query is using linq.






linq







share|improve this question




















  • 1





    so you don't want a left join...

    – Florian
    Nov 26 '18 at 8:44














0












0








0








I have 2 tables:



A {

    IDA

    propA1

    propA2

}

B {

    IDA,

    IDB,

    propB1,

    propB2

}


I want to get all records from table A such that IDA is not contained in table B where IDB = "someValue".
The query is using linq.






linq







share|improve this question
















I have 2 tables:



A {

    IDA

    propA1

    propA2

}

B {

    IDA,

    IDB,

    propB1,

    propB2

}


I want to get all records from table A such that IDA is not contained in table B where IDB = "someValue".
The query is using linq.






linq




linq






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited Nov 26 '18 at 8:24









jarlh

29.1k52138




29.1k52138










asked Nov 26 '18 at 8:21









user4675862user4675862

205




205








  • 1





    so you don't want a left join...

    – Florian
    Nov 26 '18 at 8:44














  • 1





    so you don't want a left join...

    – Florian
    Nov 26 '18 at 8:44








1




1





so you don't want a left join...

– Florian
Nov 26 '18 at 8:44





so you don't want a left join...

– Florian
Nov 26 '18 at 8:44












1 Answer
1






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oldest

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0














I assume you're using Linq on C#.



var someIDAs = B.Where(b => b.IDB == "someValue").Select(b => b.IDA);

var result = A.Where(a => !someIDAs.Contains(a.IDA));


Edit: And, as Florian says, that's something different than what is called left join.






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    0














    I assume you're using Linq on C#.



    var someIDAs = B.Where(b => b.IDB == "someValue").Select(b => b.IDA);
    
var result = A.Where(a => !someIDAs.Contains(a.IDA));


    Edit: And, as Florian says, that's something different than what is called left join.






    share|improve this answer






























      0














      I assume you're using Linq on C#.



      var someIDAs = B.Where(b => b.IDB == "someValue").Select(b => b.IDA);
      
var result = A.Where(a => !someIDAs.Contains(a.IDA));


      Edit: And, as Florian says, that's something different than what is called left join.






      share|improve this answer




























        0












        0








        0







        I assume you're using Linq on C#.



        var someIDAs = B.Where(b => b.IDB == "someValue").Select(b => b.IDA);
        
var result = A.Where(a => !someIDAs.Contains(a.IDA));


        Edit: And, as Florian says, that's something different than what is called left join.






        share|improve this answer















        I assume you're using Linq on C#.



        var someIDAs = B.Where(b => b.IDB == "someValue").Select(b => b.IDA);
        
var result = A.Where(a => !someIDAs.Contains(a.IDA));


        Edit: And, as Florian says, that's something different than what is called left join.







        share|improve this answer














        share|improve this answer



        share|improve this answer








        edited Nov 26 '18 at 8:56

























        answered Nov 26 '18 at 8:44









        ŌHARA KazutakaŌHARA Kazutaka

        567




        567
































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