Question

我有一张这样的表：

tblMembers
ID   Credit  Is_Member
---  ---     --- 
1    45      True
2    20      False
3    25      True
4    -10     True
5    -5      False
6    13      True

如何创建一个视图，显示<最低正值值信用和 Is_Member =“True”的记录？

Answer 1

select min(credit) 
from tblMembers
where Is_Member = 'true'
    and credit > 0

...如果这是作业，请将其标记为（因为答案可能不同）。

修改

没有正确阅读问题。

select * from tblMembers where credit = (select min(credit) from tblMembers where credit > 0 and Is_Member = 'true') and Is_Member = 'true'

...您需要在两个位置检查Is_Member ='true'，因为最低的信用评分可能不是会员（这将不会产生任何结果）并且非会员和会员可能会分享最低分数但仅会员应该出示。

Answer 2

可能有多条记录符合此标准......

SELECT *
FROM tblMembers
WHERE Credit = (
    SELECT  MIN(Credit)
    WHERE   Credit > 0
        AND Is_Member = 'True'
)

Answer 3

您使用的查询类似于：

SELECT *
FROM tblMembers
WHERE Credit = (SELECT MIN(Credit)
    FROM tblMembers
    WHERE Is_Member = TRUE AND Credit > 0)
AND Is_Member = TRUE

请注意，可以为最低正值绑定多行，因此您可能会获得多个结果。

Answer 4

SELECT * FROM tblMembers
WHERE Credit = 
(SELECT MIN(Credit) FROM tblMembers WHERE Credit > 0 AND Is_Member = 'True')
AND Is_Member = 'True'

请注意，如果您有多个具有相同（最低）点数的行，则会返回多行。

Answer 5

您可能有多条符合您标准的记录。如果您只想要一行：

create view PositiveCreditMember
as
select top 1
    ID
,   credit
,   is_member
from
    tblMembers
where 
    credit in (
      select
         min(Credit) 
      from
         tblMembers
      where
        credit > 0
        and is_member = 'True'
    )
    and is_member = 'True'
order by ID

Answer 6

我错过了什么吗？这似乎很简单：

select min(Credit) as Credit 
from tblMembers 
where Is_Member = 'True' and Credit >= 0

Answer 7

SELECT MIN(Credit), ID FROM tblMembers WHERE Is_Member="True"
GROUP BY ID HAVING MIN(Credit) > 0

但是，我认为我可能会过度简化这一点。使用风险自负。

Answer 8

或

select * from credit
where is_member = 'true'
and   credit > 0
order by credit
limit 1

又名

select top 1 * from credit
where is_member = 'true'
and   credit > 0
order by credit

取决于您的SQL风格。这只给出了一条记录;正如其他人所说，可能有多个记录具有最小值。

Answer 9

怎么样：

CREATE VIEW vwXYZ
AS
SELECT TOP 1 *
FROM tblMembers
WHERE [Is_Member] = 1
AND Credit > 0
ORDER BY Credit;

这消除了子查询。

Answer 10

如果您想随机匹配其中一行：

select top 1 * from tblMembers where Is_Member = 1 order by credit

或者如果你想要所有匹配的行：

select top 1 with ties * from tblMembers where Is_Member = 1 order by credit

SQL Server最小值为所有正值

10 个答案: