EF6 生成的 SQL 是无效的 SQL 服务器端答案

【问题标题】：EF6 generated SQL is not valid SQL server sideEF6 生成的 SQL 是无效的 SQL 服务器端
【发布时间】：2019-11-06 14:57:20
【问题描述】：

这听起来很疯狂 - 但我观察到的事实如下：我有一个使用 EF6 连接到 SQL 服务器的 apsx mvc 应用程序。有时我会在底层生成的 SQL 上遇到异常。喜欢：

关键字'AS'附近的语法不正确”和“附近的语法不正确 '[扩展1]'

（以及它的变体）

在我看来，这不应该发生在像 EF 这样的框架中。

幸运的是，我引入了一个 SQL 拦截器（如 https://docs.microsoft.com/en-us/ef/ef6/fundamentals/logging-and-interception），让我有机会在执行之前查看 SQL。我的第一步是检查生成的 SQL - 这看起来很正常。在另一个步骤中，我在 SQL 服务器上附加了一个分析器！你猜怎么着——截获日志的 SQL 与 profiler 中记录的 SQL 不匹配。（声音 fubar，但它是观察者）到目前为止的结论是：SQL 中的单个字符不时发生变化（在观察到的情况下，逗号变成了换页符。）

互联网上是否有人知道这可能是什么背景？

更新 1：（要求的信息）

=== EF 代码 ===

public Customer GetById(string id)
{
    return DbContext.Customers.Include("Address").FirstOrDefault(a => a.Id == id);
}

=== 来自拦截器 ===

2019-11-06 09:07:14.471 +01:00 [Interceptors.SqlLogInterceptor] [44] [<<username>>] [Debug] SELECT 
     [Limit1].[AddressTypeId] AS [AddressTypeId], 
    [Limit1].[Id] AS [Id], 
    [Limit1].[AddressId] AS [AddressId], 
    [Limit1].[ShowPrebooking] AS [ShowPrebooking], 
    [Limit1].[Id1] AS [Id1], 
    [Limit1].[Name1] AS [Name1], 
    [Limit1].[Name2] AS [Name2], 
    [Limit1].[Address1] AS [Address1], 
    [Limit1].[Address2] AS [Address2], 
    [Limit1].[HouseNumber] AS [HouseNumber], 
    [Limit1].[PostCode] AS [PostCode], 
    [Limit1].[City] AS [City], 
    [Limit1].[State] AS [State], 
    [Limit1].[CountryCode] AS [CountryCode], 
    [Limit1].[ContactName] AS [ContactName], 
    [Limit1].[Email] AS [Email], 
    [Limit1].[Phone] AS [Phone], 
    [Limit1].[Mobile] AS [Mobile], 
    [Limit1].[CreatedByUserId] AS [CreatedByUserId], 
    [Limit1].[CreatedDateTime] AS [CreatedDateTime], 
    [Limit1].[UpdatedByUserId] AS [UpdatedByUserId], 
    [Limit1].[UpdatedDateTime] AS [UpdatedDateTime], 
    [Limit1].[DeliveryDescription] AS [DeliveryDescription], 
    [Limit1].[OpeningHoursTo] AS [OpeningHoursTo], 
    [Limit1].[OpeningHoursFrom] AS [OpeningHoursFrom]
    FROM ( SELECT TOP (1) 
        [Extent1].[Id] AS [Id], 
        [Extent1].[AddressId] AS [AddressId], 
        [Extent1].[ShowPrebooking] AS [ShowPrebooking], 
        [Extent2].[Id] AS [Id1], 
        [Extent2].[Name1] AS [Name1], 
        [Extent2].[Name2] AS [Name2], 
        [Extent2].[Address1] AS [Address1], 
        [Extent2].[Address2] AS [Address2], 
        [Extent2].[HouseNumber] AS [HouseNumber], 
        [Extent2].[PostCode] AS [PostCode], 
        [Extent2].[City] AS [City], 
        [Extent2].[State] AS [State], 
        [Extent2].[CountryCode] AS [CountryCode], 
        [Extent2].[ContactName] AS [ContactName], 
        [Extent2].[Email] AS [Email], 
        [Extent2].[Phone] AS [Phone], 
        [Extent2].[Mobile] AS [Mobile], 
        [Extent2].[AddressTypeId] AS [AddressTypeId], 
        [Extent2].[CreatedByUserId] AS [CreatedByUserId], 
        [Extent2].[CreatedDateTime] AS [CreatedDateTime], 
        [Extent2].[UpdatedByUserId] AS [UpdatedByUserId], 
        [Extent2].[UpdatedDateTime] AS [UpdatedDateTime], 
        [Extent2].[DeliveryDescription] AS [DeliveryDescription], 
        [Extent2].[OpeningHoursTo] AS [OpeningHoursTo], 
        [Extent2].[OpeningHoursFrom] AS [OpeningHoursFrom]
        FROM  [dbo].[Customers] AS [Extent1]
        INNER JOIN [dbo].[Addresses] AS [Extent2] ON [Extent1].[AddressId] = [Extent2].[Id]
        WHERE [Extent1].[Id] = @p__linq__0
    )  AS [Limit1]
2019-11-06 09:07:14.471 +01:00 [Yourleman.Ef.Interceptors.SqlLogInterceptor] [44] [<<username>>] [Debug] -- Failed in 1 ms with error: Incorrect syntax near 'Limit1'.
Incorrect syntax near the keyword 'AS'.

=== 来自分析器的跟踪 ===

exec sp_executesql N'SELECT 
    [Limit1].[AddressTypeId] AS [AddressTypeId], 
    [Limit1].[Id] AS [Id], 
    [Limit1].[AddressId] AS [AddressId], 
    [Limit1].[ShowPrebooking] AS [ShowPrebooking], 
    [Limit1].[Id1] AS [Id1], 
    [Limit1].[Name1] AS [Name1], 
    [Limit1].[Name2] AS [Name2], 
    [Limit1].[Address1] AS [Address1], 
    [Limit1].[Address2] AS [Address2], 
    [Limit1].[HouseNumber] AS [HouseNumber], 
    [Limit1].[PostCode] AS [PostCode], 
    [Limit1].[City] AS [City], 
    [Limit1].[State] AS [State], 
    [Limit1].[CountryCode] AS [CountryCode], 
    [Limit1].[ContactName] AS [ContactName], 
    [Limit1].[Email] AS [Email], 
    [Limit1].[Phone] AS [Phone], 
    [Limit1].[Mobile] AS [Mobile], 
    [Limit1].[CreatedByUserId] AS [CreatedByUserId], 
    [Limit1].[CreatedDateTime] AS [CreatedDateTime], 
    [Limit1].[UpdatedByUserId] AS [UpdatedByUserId], 
    [Limit1].[UpdatedDateTime] AS [UpdatedDateTime], 
    [Limit1].[DeliveryDescription] AS [DeliveryDescription], 
    [Limit1].[OpeningHoursTo] AS [OpeningHoursTo] 
    [Limit1].[OpeningHoursFrom] AS [OpeningHoursFrom]
    FROM ( SELECT TOP (1) 
        [Extent1].[Id] AS [Id], 
        [Extent1].[AddressId] AS [AddressId], 
        [Extent1].[ShowPrebooking] AS [ShowPrebooking], 
        [Extent2].[Id] AS [Id1], 
        [Extent2].[Name1] AS [Name1], 
        [Extent2].[Name2] AS [Name2], 
        [Extent2].[Address1] AS [Address1], 
        [Extent2].[Address2] AS [Address2], 
        [Extent2].[HouseNumber] AS [HouseNumber], 
        [Extent2].[PostCode] AS [PostCode], 
        [Extent2].[City] AS [City], 
        [Extent2].[State] AS [State], 
        [Extent2].[CountryCode] AS [CountryCode], 
        [Extent2].[ContactName] AS [ContactName], 
        [Extent2].[Email] AS [Email], 
        [Extent2].[Phone] AS [Phone], 
        [Extent2].[Mobile] AS [Mobile], 
        [Extent2].[AddressTypeId] AS [AddressTypeId], 
        [Extent2].[CreatedByUserId] AS [CreatedByUserId], 
        [Extent2].[CreatedDateTime] AS [CreatedDateTime], 
        [Extent2].[UpdatedByUserId] AS [UpdatedByUserId], 
        [Extent2].[UpdatedDateTime] AS [UpdatedDateTime], 
        [Extent2].[DeliveryDescription] AS [DeliveryDescription], 
        [Extent2].[OpeningHoursTo] AS [OpeningHoursTo], 
        [Extent2].[OpeningHoursFrom] AS [OpeningHoursFrom]
        FROM  [dbo].[Customers] AS [Extent1]
        INNER JOIN [dbo].[Addresses] AS [Extent2] ON [Extent1].[AddressId] = [Extent2].[Id]
        WHERE [Extent1].[Id] = @p__linq__0
    )  AS [Limit1]',N'@p__linq__0 nvarchar(4000)',@p__linq__0=N'2341234'

检查字节显示 [OpeningHoursTo] 之后有一个换页符 (\u000C)

【问题讨论】：

这是一个随机错误，还是仅针对特定查询重复？就个人而言，我不使用 EF，因此我可能无法提供答案，但是，如果您可以发布导致这些错误的生成 SQL 语句之一，那么某人可能会看到您错过的内容。
您能否发布一个示例 EF 查询以及生成的 SQL？您是否还可以在执行代码时检查 SQL Profiler 提供的内容？
请注意，SQL Profiler 实际上并没有完全按照它们传入的方式记录语句——特别是对于 RPC 调用（即带有参数的语句，这是 EF 将生成的大部分语句）实际参数值被格式化为 T-SQL 文字，即使它们实际上是作为底层 TDS 流中的二进制值传递的。所有这些都是一种冗长的说法，即 Profiler 也不总是显示字面意思。无论如何，准确的比较都需要您看到的实际陈述。
在@JeroenMostert 所说的基础上，您能否在服务器本身上运行跟踪并捕获正在执行的实际语句？
@zohar 它是随机的 - 在上面找不到模式。

标签： .net sql-server entity-framework-6

【解决方案1】：

瞧，在 2 月 3 日，错误突然返回。我们生产服务器的所有流量似乎都受到了影响，我们的客户会遇到随机错误。

在托管网站的服务器上使用日志文件和 Wireshark，我们可以排除该特定服务器，因为 TCP 包中的数据是正确的。我们还可以排除数据库服务器和另一个应用程序服务器，因为对这两个服务器的请求会以同样的方式失败。

最终，Infrastructure 能够将问题与网络中交换机上的故障端口隔离开来。禁用此端口后，问题立即得到解决。

【讨论】：