Question

我正在尝试从表格中选择特定的行。一切都很好，但最后选择的分钟无效。因此，在进行整个选择后，我需要最小支腿编号。

SELECT cashier.* , legs.* ,cashier.id as cashier, 
cashier.cashierNumber as cashierNum ,cashier.fullName as cashier
FROM myTable
INNER JOIN  legs ON main.main= legs.legMain 
INNER JOIN  cashier ON legs.cashier = cashier.id 
WHERE legs.RRZZFrom ='RR' 
AND legs.LegNumber = (SELECT Min(legs.LegNumber) FROM legs)

Answer 1

audit::inspec

Answer 2

您可能想尝试使用cte。

with cte as (
  select min(LegNumber) as minLegNum from legs
)SELECT cashier.* , legs.* ,cashier.id as cashier, 
    cashier.cashierNumber as cashierNum ,cashier.fullName as cashier
    FROM myTable
    INNER JOIN  legs ON main.main= legs.legMain 
    INNER JOIN  cashier ON legs.cashier = cashier.id 
    INNER JOIN cte c on c.minLegNum = legs.LegNumber
    WHERE legs.RRZZFrom ='RR'

Answer 3

您是否仅从所选数据中查找MIN支路编号？在这种情况下，如下所示：

WITH Details
AS
(
    SELECT cashier.* , legs.* ,cashier.id as cashier, 
    cashier.cashierNumber as cashierNum ,cashier.fullName as cashier
    FROM myTable
    INNER JOIN  legs ON main.main= legs.legMain 
    INNER JOIN  cashier ON legs.cashier = cashier.id 
    WHERE legs.RRZZFrom ='RR' 
)
SELECT d.*
FROM Details AS d
WHERE d.LegNumber = (SELECT MIN(d2.LegNumber) FROM Details AS d2);

由于我不知道表的布局，因此不确定是否需要在此处为其他任何列作为别名。

Answer 4

尝试一下：

WITH DataSource AS
(
    SELECT cashier.* 
          ,legs.* 
          ,cashier.id as cashier
          ,cashier.cashierNumber as cashierNum 
          ,cashier.fullName as cashier
          ,MIN(legs.LegNumber) OVER() AS [MinLegNUmber]
    FROM myTable
    INNER JOIN  legs 
        ON main.main= legs.legMain 
    INNER JOIN  cashier 
        ON legs.cashier = cashier.id 
    WHERE legs.RRZZFrom ='RR' 
)
SELECT *
FROM DataSource
WHERE LegNumber = [MinLegNUmber];

想法是使用OVER()子句计算选择每一行之后的最小值：

MIN(legs.LegNumber) OVER()

然后在外部查询中仅返回与此值匹配的行。

OVER子句是一种特别强大的语法，它允许对给定的一组值执行操作（排序，聚合）。 OVER()语法表示整个实体。

使用（sub Select）从表格中选择最小值

4 个答案: