TSQL仅显示第一行 [英] TSQL show only first row

问题描述

我有以下TSQL查询:

I have the following TSQL query:

SELECT DISTINCT MyTable1.Date
  FROM MyTable1 
INNER JOIN MyTable2 
ON MyTable1.Id = MyTable2.Id
WHERE Name = 'John' ORDER BY MyTable1.Date DESC

它检索一长串的日期，但是我只需要第一个，即第一行中的一个.

It retrieves a long list of Dates, but I only need the first one, the one in the first row.

我如何得到它?

非常感谢！

推荐答案

在SQL Server中，您可以使用

In SQL Server you can use TOP:

SELECT TOP 1 MyTable1.Date
FROM MyTable1 
INNER JOIN MyTable2 
  ON MyTable1.Id = MyTable2.Id
WHERE Name = 'John' 
ORDER BY MyTable1.Date DESC

如果您需要使用 DISTINCT ，则可以使用:

If you need to use DISTINCT, then you can use:

SELECT TOP 1 x.Date
FROM
(
   SELECT DISTINCT MyTable1.Date
   FROM MyTable1 
   INNER JOIN MyTable2 
     ON MyTable1.Id = MyTable2.Id
    WHERE Name = 'John' 
) x
ORDER BY x.Date DESC

甚至:

SELECT MAX(MyTable1.Date)
FROM MyTable1 
INNER JOIN MyTable2 
  ON MyTable1.Id = MyTable2.Id
WHERE Name = 'John' 
--ORDER BY MyTable1.Date DESC

这篇关于TSQL仅显示第一行的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！