Question

我试图从一个时间段内得分最多的数据库中返回一个人，

我的数据库表有3个文件，人，日期和点数，

积分将单独添加给人。

我将在数据库中有大约30个人和点表中的无限条目

有人可以帮我处理一个SQL查询，以返回一个具有最大点数的人。

我曾经想过要分两步完成这项工作，1，为所选时期的每个人提供点数总和但不知道如何获得得分最多的人

编辑：我有以下代码将数据输入数据库

        OleDbCommand com = new OleDbCommand("INSERT INTO FlightPoints ([Person], [Flight], [Date_Added], [Points], [Reason]) VALUES (?, ?, ?, ?, ?)", Program.DB_CONNECTION); // add the information into the database
        com.Parameters.Add(new OleDbParameter("", cadet[CadetcomboBox.SelectedIndex].ID));
        com.Parameters.Add(new OleDbParameter("", cadet[CadetcomboBox.SelectedIndex].Flight.ID));
        com.Parameters.Add(new OleDbParameter("", DateTime.Today));
        com.Parameters.Add(new OleDbParameter("", PointsnumericUpDown.Value));
        com.Parameters.Add(new OleDbParameter("", ReasontextBox.Text));

        com.ExecuteNonQuery();

另外两个或两个以上的人实际上可以拥有相同的总分数。我怎么能让所有人得到同样的最高分呢？

Answer 1

如果我理解正确，你有两个表：

SELECT TOP 1 PersonName FROM 
(
SELECT  
    PersonName,Points       
FROM
    PersonTable
        INNER JOIN (
            SELECT
                PersonId, SUM(Points) AS Points
            FROM 
                PersonPoint 
            WHERE               
                PointDate BETWEEN @StartDate AND @EndDate
            GROUP BY PersonId               
        ) AS MaxPoints
            ON 
               MaxPoints.PersonId = PersonTable.PersonId
) q
ORDER BY Points DESC

编辑：考虑到两个或更多人可以拥有相同数量的点数，查询将如下所示，结果如下所示，您可以使用光标选择最高分数：

SELECT PersonName FROM 
(
SELECT  
    PersonName,Points       
FROM
    PersonTable
        INNER JOIN (
            SELECT
                PersonId, SUM(Points) AS Points
            FROM 
                PersonPoint 
            WHERE               
                PointDate  BETWEEN  @StartDate AND @EndDate
            GROUP BY PersonId               
        ) AS MaxPoints
            ON 
               MaxPoints.PersonId = PersonTable.PersonId
) q
ORDER BY Points DESC

Answer 2

SELECT TOP 1 points_person, Sum(points_value)
FROM dbo.points
GROUP BY points_person
ORDER BY Sum(points_value) DESC

Answer 3

如果我的布局正确，这适用于SQL Server。

create table #Points
(
    [Person] varchar(50) not null,
    [Date] DateTime not null,
    [Points] int not null
)

insert into #Points (Person,Date,Points) values ('Hans',GETDATE(),1)
insert into #Points (Person,Date,Points) values ('Hans',GETDATE(),2)
insert into #Points (Person,Date,Points) values ('Hans',GETDATE(),3)
insert into #Points (Person,Date,Points) values ('Hans',GETDATE(),4)
insert into #Points (Person,Date,Points) values ('Fritz',GETDATE(),5)

select top 1 Person, Sum(Points)
from #Points
where Date>='2015-02-26 00:00:00' and Date<='2015-02-26 23:59:59'
group by Person
order by 2 desc

drop table #Points

从数据库中查找最大总和

3 个答案: