Question

我想从下表中获取最后4个星期五的日期。取决于用户输入计数将存储在另一个表中，并根据我想要获取日期的值。例如，如果计数为5，我想得到最后5个星期五的日期。

---------------------------------------------
  Id        |           fridaydate
---------------------------------------------
   1        |   2014-08-15 11:46:00.000   |

   2        |   2014-08-22 11:46:00.000   |

   3        |   2014-08-08 11:46:00.000   |

   4        |   2014-08-01 11:46:00.000   |

   5        |   2014-07-25 11:46:00.000   |

   6        |   2014-07-18 11:46:00.000   |

   7        |   2014-07-11 11:46:00.000   |

Answer 1

使用以下格式：

DECLARE @D INT= 5    -- User Input value

SELECT TOP (@D) *
FROM YourTable

您可以在存储过程中使用上述查询，如下所示：

Create Procedure YourProcedureName 
  @D int
as Begin
    SELECT TOP (@D) *
    FROM YourTable
    Order by fridaydate Desc
End

Answer 2

这样的事情会：

select ca.*
from dbo.AnotherTable a
    cross apply (
        select top (a.FridayCount) *
        from dbo.FridayTable ft
        where ft.FridayDate <= getdate()
        order by ft.FridayDate desc
    ) ca
where a.UserId = @SomeUserId
order by ca.FridayDate desc;

Answer 3

SELECT TOP @YourCount fridaydate FROM Table ORDER BY Id DESC

Answer 4

SELECT top 5 datefield
FROM table
WHERE lower(datename(dw, datefield))='friday'
GROUP BY datefield
ORDER BY datefield desc

获取最后4个星期五日期的SQL查询

4 个答案: