Question

我试图选择拥有最早SDate的员工的姓名。我尝试了以下方法：

SELECT [name]
          FROM [employee]
          where [dept] in ('Finance', 'HR', 'IT')
          and [SDate] = min([SDate]);

我被抛出了一个错误。这并不奇怪，因为我在where子句中有一个聚合函数。所以，我修改了它：

SELECT [name]
          FROM [employee]
          where [dept] in ('Finance', 'HR', 'IT')
          group by [name]
          having [SDate] = min([SDate]);

但它仍然无法奏效。我应该如何构建我的T-SQL，以便获得具有最小SDate的员工的姓名？

Answer 1

使用order by和top：

SELECT top 1 [name]
FROM [employee]
WHERE [dept] in ('Finance', 'HR', 'IT')
ORDER BY sdate desc;

Answer 2

DECLARE @minDate Date
SELECT
    @mindate=MIN(sDate) 
FROM 
    employee E
WHERE 
    [dept] IN ('Finance', 'HR', 'IT');

SELECT
    [name]
FROM
    [employee]
WHERE
    [dept] IN ('Finance', 'HR', 'IT')
    and [sDate] = @minDate;

如何以最低条件查询？

2 个答案: