左加入或OR條件

Question

如何在實體框架中表示以下LEFT JOIN？

SELECT * FROM a 
LEFT JOIN b ON 
(a.UserId = b.Field1 AND b.Field2 = SOME_VARIABLE) 
OR (a.UserId = b.Field2 AND b.Field1 = SOME_VARIABLE) 

爲AND的I知道我可以使用複雜的匿名類型和EQUALS但我無法弄清楚如何處理OR S'

Answer 1

var query = from a in context.aTable 
      select new { 
       A = a, 
       B = (from b in context.bTable 
        where (a.UserId == b.Field1 && b.Field2 == SOME_VARIABLE) || 
          (a.UserId == b.Field2 && b.Field1 == SOME_VARIABLE) 
        select b 
        ).DefaultIfEmpty() 
      } 

根據您的需要，您可以忽略DefaultIfEmpty。