私は SQL の経験が豊富ですが、LINQ にはかなり慣れていないため、次の MySQL クエリを LINQ に変換するのに苦労しています。Entityフレームワークを使用したASP.net MVCプロジェクトで使用するために、次のものをLINQに変換するのを手伝ってくれる人はいますか?
SELECT
S.Submission_ID,
P.Photo_ID,
C2.Contract_Name,
J.Job_Number,
D.Device_Name,
A.`Display_Name`,
S.Submission_Status,
S.Submission_JobRef,
S.Created,
TRUE
FROM
Submission S
LEFT JOIN Job J ON S.`Job_ID` = J.`Job_ID`
LEFT JOIN Contract C2 ON J.`Contract_ID` = C2.`Contract_ID`
INNER JOIN Submission_Status SS ON S.`Submission_Status` = SS.`ID`
INNER JOIN Device D ON S.`Device_ID` = D.`Device_ID`
INNER JOIN ACTION A ON S.`Action_ID` = A.`Action_ID`
INNER JOIN (
SELECT
MIN(P.Photo_ID) AS Photo_ID,
P.Submission_ID
FROM
Photo P
GROUP BY
P.`Submission_ID`) P ON S.`Submission_ID` = P.Submission_ID
WHERE
S.`Submission_Status` <> 3 AND
(LOCATE(@Criteria, C2.`Contract_Name`) > 0 OR
LOCATE(@Criteria, J.`Job_Number`) > 0 OR
LOCATE(@Criteria, D.`Device_Name`) > 0 OR
LOCATE(@Criteria, A.`Display_Name`) > 0 OR
LOCATE(@Criteria, SS.`Value`) > 0 OR
LOCATE(@Criteria, S.`Submission_JobRef`) > 0)
ORDER BY
S.`Submission_ID` DESC
複数の結合とサブクエリに頭を悩ませようとしましたが、行き詰まりました。これは私がこれまでに持っているものです...明らかに、それは機能していないか完全ではありません!!
Dim results = From S In db.Submissions
Join P In db.Photos On S.Submission_ID Equals P.Submission_ID
Group Join J In db.Jobs On S.Job_ID Equals J.Job_ID
Into Job = Group
Join J In db.Jobs On S.Job_ID Equals J.Job_ID
Group By P.Submission_ID
Into SubmissionPhotoID = Min(P.Photo_ID)
Select New With {.Submission_ID = Submission_ID,
.Photo_ID = SubmissionPhotoID,
.Contract_Name = If(IsNothing(S.Job), "", S.Job.Contract.Contract_Name),
.Job_Number = If(IsNothing(S.Job), "", S.Job.Job_Number),
.Device_Name = S.Device.Device_Name,
.Action_Name = S.Action.Display_Name,
.Submission_Status = S.Submission_Status1.ID,
.Submission_JobRef = S.Submission_JobRef,
.Created = S.Created,
.CanEdit = bolCanEdit}
Order By S.Submission_ID
Skip param.iDisplayStart
Take param.iDisplayLength
上記のヘルプまたはガイダンスをいただければ幸いです。
編集
参考までに、上記のクエリで使用されるエンティティを定義するモデルのクラスを次に示します。（質問に関係のないいくつかのフィールドを省略しました）。
Partial Public Class Submission
Public Property Submission_ID As Integer
Public Property Job_ID As Nullable(Of Integer)
Public Property Device_ID As Integer
Public Property Action_ID As Integer
Public Property Submission_Status As Nullable(Of Integer)
Public Property Submission_JobRef As String
Public Property Created As Nullable(Of Date)
Public Overridable Property Action As Action
Public Overridable Property Device As Device
Public Overridable Property Job As Job
Public Overridable Property Photos As ICollection(Of Photo) = New HashSet(Of Photo)
Public Overridable Property Submission_Status1 As Submission_Status
End Class
Partial Public Class Job
Public Property Job_ID As Integer
Public Property Contract_ID As Nullable(Of Integer)
Public Property Job_Number As String
Public Overridable Property Contract As Contract
Public Overridable Property Submissions As ICollection(Of Submission) = New HashSet(Of Submission)
End Class
Partial Public Class Contract
Public Property Contract_ID As Integer
Public Property Contract_Name As String
Public Overridable Property Jobs As ICollection(Of Job) = New HashSet(Of Job)
End Class
Partial Public Class Submission_Status
Public Property ID As Integer
Public Property Value As String
Public Overridable Property Submissions As ICollection(Of Submission) = New HashSet(Of Submission)
End Class
Partial Public Class Device
Public Property Device_ID As Integer
Public Property Device_Name As String
Public Overridable Property Submissions As ICollection(Of Submission) = New HashSet(Of Submission)
End Class
Partial Public Class Action
Public Property Action_ID As Integer
Public Property Display_Name As String
Public Overridable Property Submissions As ICollection(Of Submission) = New HashSet(Of Submission)
End Class
Partial Public Class Photo
Public Property Photo_ID As Integer
Public Property Submission_ID As Integer
Public Overridable Property Submission As Submission
End Class