Linq with EF core 2.2 Condition with where Clause FK and PK

Question

嗨，我在使用帶有 FK 和 PK 的 where 子句時遇到問題，因為來自 InstalltionÍnformation 的 FK 是 Object。 我無法理解。 i => i.ImportRunID是 iqueryable 並且不能轉換為 int ImportRuns.ImportRunId

var Aggnone = context.ImportRuns.Select(IR => new
                        {
                            ImportRunId = IR.ImportRunId,
                            ExtractedDate = IR.ExtractedDate,
                            ProcessDate = IR.ProcessDate,
                            ProcessResult = IR.ProcessResult,
                            FailureDescription = IR.ProcessResult,
                            InstallationInformationIDFK = context.InstallationInformation.Select(II => new
                            {
                                InstallationInformationID = II.InstallationInformationID,
                                LicenceKey = II.LicenceKey,
                                ProductVersion = II.ProductVersion,
                                ProductName = II.ProductName,
                                CompanyName = II.CompanyName,
                                Timestamp = II.Timestamp
                            })
                        }).Where(x => x.ImportRunId == context.InstallationInformation.Select(i => i.ImportRunID);

MSSQL中的等價物（應該是什么）

 Select * from ImportRuns as IR
 left join InstallationInformation as II 
 on IR.ImportRunId = II.ImportRunId

有沒有辦法解決這個問題？

Answer 1

嘗試使用

context.InstallationInformation.FirstOrDefault(i => i.ImportRunID).InstallationInformationID 

代替

context.InstallationInformation.Select(i => i.ImportRunID)