Question

// Query all records
var q =
dc.tblHelpCentreQuestions.Where(question => question.userID == UserID).Where(question => question.awaitingUserResponse == true || question.awaitingSupportResponse == true).
OrderBy(s => s.awaitingUserResponse).ThenBy(s => s.dateSubmitted).
GroupJoin(
    dc.tblHelpCentreReplies,
    question => question.ID,
    replies => replies.ticketID,
    (question, replies) => new { Question = question, RepliesCount = replies.Count() }
);

无论我通过查询放置订单，它似乎只是随机排序。

编辑：结尾处的订单结果相同：

// Query all records
var q =
dc.tblHelpCentreQuestions.Where(question => question.userID == UserID).Where(question => question.awaitingUserResponse == true || question.awaitingSupportResponse == true).
GroupJoin(
    dc.tblHelpCentreReplies,
    question => question.ID,
    replies => replies.ticketID,
    (question, replies) => new { Question = question, RepliesCount = replies.Count() }
).OrderBy(s => s.Question.awaitingUserResponse).ThenBy(s => s.Question.dateSubmitted);

编辑：生成的SQL

exec sp_executesql N'SELECT [t2].[ID], [t2].[catID], [t2].[subject], [t2].[question], [t2].[userID], [t2].[dateSubmitted], [t2].[isUrgent], [t2].[emailMe], [t2].[awaitingSupportResponse], [t2].[awaitingUserResponse], [t2].[lastReply], [t2].[stopWatchTotalMins], [t2].[isStopWatchOn], [t2].[stopWatchStart], [t2].[priorityLevel], [t2].[value] AS [RepliesCount]
FROM (
    SELECT [t0].[ID], [t0].[catID], [t0].[subject], [t0].[question], [t0].[userID], [t0].[dateSubmitted], [t0].[isUrgent], [t0].[emailMe], [t0].[awaitingSupportResponse], [t0].[awaitingUserResponse], [t0].[lastReply], [t0].[stopWatchTotalMins], [t0].[isStopWatchOn], [t0].[stopWatchStart], [t0].[priorityLevel], (
        SELECT COUNT(*)
        FROM [dbo].[tblHelpCentreReplies] AS [t1]
        WHERE ([t0].[ID]) = [t1].[ticketID]
        ) AS [value]
    FROM [dbo].[tblHelpCentreQuestions] AS [t0]
    ) AS [t2]
WHERE (([t2].[awaitingUserResponse] = @p0) OR ([t2].[awaitingSupportResponse] = @p1)) AND ([t2].[userID] = @p2)
ORDER BY [t2].[awaitingUserResponse], [t2].[dateSubmitted]', N'@p0 int,@p1 int,@p2 int', @p0 = 1, @p1 = 1, @p2 = 81

我通过数据库运行代码并正确返回结果，因此它必须是其他奇怪的东西，因为代码非常简单，但不要介意，感谢所有人的帮助，我学会了很多新事物都有这个问题！

Answer 1

这是LINQ to SQL吗？我怀疑问题是你在分组之前订购。你可以试试这个：

var q = dc.tblHelpCentreQuestions .Where(question => question.userID == UserID) .Where(question => question.awaitingUserResponse || question.awaitingSupportResponse) .GroupJoin(dc.tblHelpCentreReplies, question => question.ID, replies => replies.ticketID, (question, replies) => new { Question = question, RepliesCount = replies.Count() }) .OrderBy(s => s.Question.awaitingUserResponse) .ThenBy(s => s.Question.dateSubmitted);

编辑：好的，如果这不起作用那么也许这是SQL分组的限制......虽然这看起来很奇怪。

您可以随时强制在客户端执行排序：

var q = dc.tblHelpCentreQuestions .Where(question => question.userID == UserID) .Where(question => question.awaitingUserResponse || question.awaitingSupportResponse) .GroupJoin(dc.tblHelpCentreReplies, question => question.ID, replies => replies.ticketID, (question, replies) => new { Question = question, RepliesCount = replies.Count() }) // Force the rest of the query to execute in .NET code (Enumerable.XXX) .AsEnumerable() .OrderBy(s => s.Question.awaitingUserResponse) .ThenBy(s => s.Question.dateSubmitted);

Answer 2

您是否尝试过将OrderBy移至最后一次操作，就在之前;？像SQL一样，如果我在订购后对它执行任何操作，我不希望收到有序集...我很想知道按顺序显示实际生成的SQL是什么。

编辑代码探索使用ToList（）强制执行，然后执行客户端排序：

var q = dc.tblHelpCentreQuestions
    .Where(question => question.userID == UserID)
    .Where(question => question.awaitingUserResponse == true || question.awaitingSupportResponse == true)
    .GroupJoin(
        dc.tblHelpCentreReplies,
        question => question.ID,
        replies => replies.ticketID,
        (question, replies) => new { Question = question, RepliesCount = replies.Count() }
    )
    .ToList()
    .OrderBy(s => s.Question.awaitingUserResponse)
    .ThenBy(s => s.Question.dateSubmitted);

Answer 3

GroupJoin很可能会覆盖订单。它可能是作为子查询实现的。如果您运行LINQ to SQL Profiler或SQL分析器以查看基础查询，它将能够阐明这一点。您是否尝试将OrderBy作为方法链中的最后一个操作？

Answer 4

如果您想订购分组问题，则需要在创建GroupJoin后执行此操作：

var q =
    dc.tblHelpCentreQuestions.Where(question => question.userID == UserID).Where(question => question.awaitingUserResponse == true || question.awaitingSupportResponse == true).
    GroupJoin(
        dc.tblHelpCentreReplies,
        question => question.ID,
        replies => replies.ticketID,
        (question, replies) => new { Question = question, RepliesCount = replies.Count() }
    ).
    AsEnumerable().
    OrderBy(s => s.Question.awaitingUserResponse).
    ThenBy(s => s.Question.dateSubmitted);

GroupJoin会有效地删除您的订单，因为它会按照您的订单收集并按问题对其进行分组。 GroupJoin不保留密钥的初始排序。

编辑：您可以通过在GroupQoin之后转换为可枚举来强制在LINQ to Objects中进行排序来消除此问题。

Answer 5

很难测试你的代码，因为我没有你的所有声明，但我怀疑你看似随机行为的原因是因为GroupJoin不保证保持订单完整。

因此，您必须在分组后进行排序。

例如：

var q = dc.tblHelpCentreQuestions .Where(question => question.userID == UserID) .Where(question => question.awaitingUserResponse == true || question.awaitingSupportResponse == true) .GroupJoin( dc.tblHelpCentreReplies, question => question.ID, replies => replies.ticketID, (question, replies) => new { Question = question, RepliesCount = replies.Count() } ) .OrderBy(s => s.Question.awaitingUserResponse) .ThenBy(s => s.Question.dateSubmitted);

Answer 6

尝试在LINQ查询后添加ToArray（）。我知道LINQ遵循惰性求值规则，并且ToArray（）迫使评估变得急切。

Linq order by不订购任何东西

编辑：结尾处的订单结果相同：

编辑：生成的SQL

6 个答案: