Sql 将select上的datetime与date only进行比较

我想根据他们的日期是否共享来比较两个日期时间。 这项工作：

SELECT *
FROM XXX
WHERE CAST(LoadDateLAG AS DATE) = CAST(LoadDateLEAD AS DATE)

但是，我想实际获得一个额外列的结果：

SELECT 
    CAST(LoadDateLAG AS DATE) = CAST(LoadDateLEAD AS DATE)
    , *
FROM XXX

后者不起作用，因为SQLServer抱怨语法无效。 有什么建议吗

结果如下：

LoadDateLAG | LoadDateLEAD | (LoadDateLAG = LoadDateLEAD) [as bit]

我需要这个功能来压缩历史记录表 -删除不必要的条目（例如，每天只保留最后一个条目）。

您可以使用：

如果您还想显示

日期

值（而不是

日期时间）

，您可以使用以下

选择

：

 SELECT 
    CAST(LoadDateLAG AS DATE) AS LoadDateLAG,
    CAST(LoadDateLEAD AS DATE) AS LoadDateLEAD,
    CASE WHEN CAST(LoadDateLAG AS DATE) = CAST(LoadDateLEAD AS DATE) THEN 1 ELSE 0 END AS isDateEquals
FROM XXX
-- WHERE CAST(LoadDateLAG AS DATE) = CAST(LoadDateLEAD AS DATE)

SELECT 
    LoadDateLAG, LoadDateLEAD,
    CASE WHEN CAST(LoadDateLAG AS DATE) = CAST(LoadDateLEAD AS DATE) THEN CAST(LoadDateLAG AS DATE) ELSE NULL END AS equalsDate
FROM XXX
-- WHERE CAST(LoadDateLAG AS DATE) = CAST(LoadDateLEAD AS DATE)

如果您想显示

日期

值（而不是1或0），如果相等，可以使用以下

选择

：

 SELECT 
    CAST(LoadDateLAG AS DATE) AS LoadDateLAG,
    CAST(LoadDateLEAD AS DATE) AS LoadDateLEAD,
    CASE WHEN CAST(LoadDateLAG AS DATE) = CAST(LoadDateLEAD AS DATE) THEN 1 ELSE 0 END AS isDateEquals
FROM XXX
-- WHERE CAST(LoadDateLAG AS DATE) = CAST(LoadDateLEAD AS DATE)

SELECT 
    LoadDateLAG, LoadDateLEAD,
    CASE WHEN CAST(LoadDateLAG AS DATE) = CAST(LoadDateLEAD AS DATE) THEN CAST(LoadDateLAG AS DATE) ELSE NULL END AS equalsDate
FROM XXX
-- WHERE CAST(LoadDateLAG AS DATE) = CAST(LoadDateLEAD AS DATE)

演示：

SQL Server 2012+

SELECT IIF(CAST(LoadDateLAG AS DATE) = CAST(LoadDateLEAD AS DATE),1,0),* FROM XXX

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你期望的结果是什么？你能举个例子吗？你希望在额外的专栏中看到什么？从你失败的尝试中，你的意图并不清楚。