Question

我有一个带有DateTime列的数据库，并希望将它与某些DateTimeOffset进行比较。 DateTime列位于（服务器）本地时间。除了对WTF它的咆哮之外，我无能为力，我喜欢经常和激烈地做，所以我现在可以跳过它。

我希望能够从我的DateTimeOffset之前的DateTime x发生的表中选择所有行。我可以假设如果它现在是服务器上的DST，那么DateTime列也在DST中，反之亦然。这些时间将被定位在'now'周围，DateTime（几乎）总是在过去的几个小时内。我会在下巴发生时对下巴进行DST更改，但在DST或非DST中解决方案不应该总是错误。

作为奖励要求，表格很大，因此对DateTime执行任何操作都是不可能的。我想的是我正在寻找相当于

的东西

DECLARE @dto datetimeoffset(4) = '12-10-25 12:32:10 +06:00';

DECLARE @dt datetime = --this is where the magic happens?

SELECT * FROM MyTable WHERE datetimecol < @dt

任何人都可以帮助我实现魔力吗？

Answer 1

您需要一个SQL CLR函数才能执行此操作。受this post的启发，我写了以下内容：

using System;
using Microsoft.SqlServer.Server;

public class UserDefinedFunctions
{
    [SqlFunction(IsDeterministic = false)]
    public static DateTime? ConvertDateTimeOffsetToLocalDateTime(DateTimeOffset? dto)
    {
        if (!dto.HasValue)
            return null;

        return dto.Value.ToLocalTime().DateTime;
    }
}

如果您愿意，可以自己编译，或者只使用以下内容进行部署，其中包含序列化二进制文件和SQL部署脚本：

EXEC sp_configure 'clr enabled', 1;
GO
RECONFIGURE
GO
CREATE ASSEMBLY [SqlClrDateTime]
FROM 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
WITH PERMISSION_SET = SAFE
GO
CREATE FUNCTION dbo.ConvertDateTimeOffsetToLocalDateTime(@dto datetimeoffset)
RETURNS datetime2
AS EXTERNAL NAME SqlClrDateTime.UserDefinedFunctions.ConvertDateTimeOffsetToLocalDateTime
GO

以下是您在场景中如何使用它的方法：

DECLARE @dto datetimeoffset(4) = '12-10-25 12:32:10 +06:00'

DECLARE @dt datetime = dbo.ConvertDateTimeOffsetToLocalDateTime(@dto) 

SELECT * FROM MyTable WHERE datetimecol < @dt

将本地DateTime与DateTimeOffset进行比较

1 个答案: