我正在尝试使用EF 6.1 Code First设置可选的多对多关系。我有一个可以拥有0个或更多基金组的合作伙伴。我已使用以下代码成功创建了映射：
HasMany(t => t.FundGroups)
.WithMany()
.Map(x =>
{
x.MapLeftKey("PartnerId");
x.MapRightKey("FundGroupId");
x.ToTable("PartnerFundGroupMap", "admin");
})
.MapToStoredProcedures(s => s.Insert(i => i.HasName("admin.InsertPartnerFundGroups")
.LeftKeyParameter(p => p.PartnerId, "PartnerId")
.RightKeyParameter(p => p.FundGroupId, "FundGroupId"))
.Delete(i => i.HasName("admin.DeletePartnerFundGroups")
.LeftKeyParameter(p => p.PartnerId, "PartnerId")
.RightKeyParameter(p => p.FundGroupId, "FundGroupId")));
问题是代码创建了一个内部联接，我没有找回没有关联基金组的实体。有没有办法强制左连接，所以我总是可以检索合作伙伴，即使基金组没有与之关联。请参阅下面生成的查询：
SELECT
[Project1].[IRSEntityTypeID1] AS [IRSEntityTypeID],
[Project1].[RegionID1] AS [RegionID],
[Project1].[CountryID1] AS [CountryID],
[Project1].[PartnershipLevelId1] AS [PartnershipLevelId],
[Project1].[PartnerID] AS [PartnerID],
[Project1].[C1] AS [C1],
[Project1].[ExternalCode] AS [ExternalCode],
[Project1].[CompanyCode] AS [CompanyCode],
[Project1].[PartnerName] AS [PartnerName],
[Project1].[EIN] AS [EIN],
[Project1].[KitCode] AS [KitCode],
[Project1].[IRSEntityTypeID] AS [IRSEntityTypeID1],
[Project1].[Address1] AS [Address1],
[Project1].[Address2] AS [Address2],
[Project1].[City] AS [City],
[Project1].[IsPartnership] AS [IsPartnership],
[Project1].[SessionId] AS [SessionId],
[Project1].[RegionID] AS [RegionID1],
[Project1].[CountryID] AS [CountryID1],
[Project1].[PostalCode] AS [PostalCode],
[Project1].[PartnershipLevelId] AS [PartnershipLevelId1],
[Project1].[C2] AS [C2],
[Project1].[C4] AS [C3],
[Project1].[C5] AS [C4],
[Project1].[Description] AS [Description],
[Project1].[C6] AS [C5],
[Project1].[C7] AS [C6],
[Project1].[CountryName] AS [CountryName],
[Project1].[C8] AS [C7],
[Project1].[C9] AS [C8],
[Project1].[RegionName] AS [RegionName],
[Project1].[C10] AS [C9],
[Project1].[C11] AS [C10],
[Project1].[IRSEntityTypeName] AS [IRSEntityTypeName],
[Project1].[C12] AS [C11],
[Project1].[C13] AS [C12],
[Project1].[C14] AS [C13],
[Project1].[C15] AS [C14],
[Project1].[C16] AS [C15],
[Project1].[FundGroupID] AS [FundGroupID],
[Project1].[C3] AS [C16],
[Project1].[FundGroupCode] AS [FundGroupCode],
[Project1].[FundGroupName] AS [FundGroupName],
[Project1].[SessionId1] AS [SessionId1],
[Project1].[CreateDate] AS [CreateDate],
[Project1].[ModifiedDate] AS [ModifiedDate]
FROM ( SELECT
[Extent1].[PartnerID] AS [PartnerID],
[Extent1].[ExternalCode] AS [ExternalCode],
[Extent1].[CompanyCode] AS [CompanyCode],
[Extent1].[PartnerName] AS [PartnerName],
[Extent1].[EIN] AS [EIN],
[Extent1].[KitCode] AS [KitCode],
[Extent1].[IRSEntityTypeID] AS [IRSEntityTypeID],
[Extent1].[Address1] AS [Address1],
[Extent1].[Address2] AS [Address2],
[Extent1].[City] AS [City],
[Extent1].[IsPartnership] AS [IsPartnership],
[Extent1].[SessionId] AS [SessionId],
[Extent1].[RegionID] AS [RegionID],
[Extent1].[CountryID] AS [CountryID],
[Extent1].[PostalCode] AS [PostalCode],
[Extent1].[PartnershipLevelId] AS [PartnershipLevelId],
[Extent2].[PartnershipLevelId] AS [PartnershipLevelId1],
[Extent2].[Description] AS [Description],
[Extent3].[CountryID] AS [CountryID1],
[Extent3].[CountryName] AS [CountryName],
[Extent4].[RegionID] AS [RegionID1],
[Extent4].[RegionName] AS [RegionName],
[Extent5].[IRSEntityTypeID] AS [IRSEntityTypeID1],
[Extent5].[IRSEntityTypeName] AS [IRSEntityTypeName],
N''3ed69e78-cbfb-4d5b-a270-85d0d62bb11c'' AS [C1],
N''FundGroups'' AS [C2],
[Join5].[FundGroupID1] AS [FundGroupID],
[Join5].[FundGroupCode] AS [FundGroupCode],
[Join5].[FundGroupName] AS [FundGroupName],
[Join5].[SessionID] AS [SessionId1],
[Join5].[CreateDate] AS [CreateDate],
[Join5].[ModifiedDate] AS [ModifiedDate],
CASE WHEN ([Join5].[PartnerId] IS NULL) THEN CAST(NULL AS varchar(1)) ELSE N''3ed69e78-cbfb-4d5b-a270-85d0d62bb11c'' END AS [C3],
N''PartnershipLevel'' AS [C4],
N''3ed69e78-cbfb-4d5b-a270-85d0d62bb11c'' AS [C5],
N''Country'' AS [C6],
N''3ed69e78-cbfb-4d5b-a270-85d0d62bb11c'' AS [C7],
N''Region'' AS [C8],
N''3ed69e78-cbfb-4d5b-a270-85d0d62bb11c'' AS [C9],
N''IRSEntityType'' AS [C10],
N''3ed69e78-cbfb-4d5b-a270-85d0d62bb11c'' AS [C11],
cast(0 as bit) AS [C12],
cast(0 as bit) AS [C13],
cast(0 as bit) AS [C14],
cast(0 as bit) AS [C15],
CASE WHEN ([Join5].[PartnerId] IS NULL) THEN CAST(NULL AS int) ELSE 1 END AS [C16]
FROM [admin].[vPartner] AS [Extent1]
INNER JOIN [admin].[PartnershipLevel] AS [Extent2] ON [Extent1].[PartnershipLevelId] = [Extent2].[PartnershipLevelId]
INNER JOIN [admin].[Country] AS [Extent3] ON [Extent1].[CountryID] = [Extent3].[CountryID]
INNER JOIN [admin].[Region] AS [Extent4] ON [Extent1].[RegionID] = [Extent4].[RegionID]
INNER JOIN [admin].[IRSEntityType] AS [Extent5] ON [Extent1].[IRSEntityTypeID] = [Extent5].[IRSEntityTypeID]
LEFT OUTER JOIN (SELECT [Extent6].[PartnerId] AS [PartnerId], [Extent7].[FundGroupID] AS [FundGroupID1], [Extent7].[FundGroupCode] AS [FundGroupCode], [Extent7].[FundGroupName] AS [FundGroupName], [Extent7].[SessionID] AS [SessionID], [Extent7].[CreateDate] AS [CreateDate], [Extent7].[ModifiedDate] AS [ModifiedDate]
FROM [admin].[PartnerFundGroupMap] AS [Extent6]
INNER JOIN [admin].[FundGroup] AS [Extent7] ON [Extent6].[FundGroupId] = [Extent7].[FundGroupID] ) AS [Join5] ON [Extent1].[PartnerID] = [Join5].[PartnerId]
WHERE [Extent1].[PartnerID] = @p__linq__0
) AS [Project1]
ORDER BY [Project1].[IRSEntityTypeID1] ASC, [Project1].[RegionID1] ASC, [Project1].[CountryID1] ASC, [Project1].[PartnershipLevelId1] ASC, [Project1].[PartnerID] ASC, [Project1].[C16] ASC',N'@p__linq__0 int',@p__linq__0=1
答案 0 :(得分：0)
我找到了这个问题。它与“多对多”映射无关，也是另一个实体所需映射的结果。感谢Dabblernl让我发布查询，在进一步检查查询后我发现了问题