I have the following weird behaviour:
public class Result
{
[Key]
public int Id { get; set; }
public int RuleId { get; set; }
public int UserId { get; set; }
[ForeignKey("RuleId")]
public virtual Rule Rule { get; set; }
[ForeignKey("UserId ")]
public virtual User User { get; set; }
}
public class Rule
{
[Key]
public int Id { get; set; }
public string Name { get; set; }
// More columns
}
public class User
{
[Key]
public int Id { get; set; }
public string Name { get; set; }
// More columns
}
If I do:
ctx.Results.AsQueryable().Select(r => new { r.Rule.Name } ).ToList();
The query executed in SQL Server does an inner join on Rule:
SELECT
[Extent1].[RuleId] AS [RuleId],
[Extent2].[Name] AS [Name]
FROM [dbo].[result] AS [Extent1]
INNER JOIN [dbo].[rule] AS [Extent2] ON [Extent1].[RuleId] = [Extent2].[Id]
BUT if I do:
ctx.Results.AsQueryable().Select(r => new { rn = r.Rule.Name, un = r.User.Name } ).ToList();
The query executed does an inner join on rule but an OUTER JOIN on User.
SELECT
[Extent1].[UserId] AS [UserId],
[Extent2].[Name] AS 开发者_C百科[Name],
[Extent3].[Name] AS [Name1]
FROM [dbo].[result] AS [Extent1]
INNER JOIN [dbo].[rule] AS [Extent2] ON [Extent1].[RuleId] = [Extent2].[Id]
LEFT OUTER JOIN [dbo].[user] AS [Extent3] ON [Extent1].[UserId] = [Extent3].[Id]
Surely this is wrong?
Answer was: Bug in entity framework. Download very latest version and they are all inner joins.
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