Question

我有一个表测量，其数据如下所示。

week   hips    wrist    abs    weight
1      26.3    6.3      24.3    100
2      25.2    6.3      23.3    96

我试图从第2周到第1周得到结果

hips    wrist    abs    weight
-1.1    0        -1      -4

我试着加入彼此的表并减去但我一直在重复。我该如何做到这一点？

Answer 1

你试过这个吗？

select mprev.hips - m.hips as hips,
       mprev.wrist - m.wrist  as wrist,
       mprev.abs - m.abs as abs,
       mprev.weight - m.weight as weight
from measurements m join
     measurements mprev
     on me.week = mprev.week + 1;

Answer 2

SELECT
 a.[hips]-b.hips as Hips
, a.wrist - b.wrist as Wrist
, a.abs - b.abs as Abs
, a.weight - b.weight as Weight
FROM
tableName a
LEFT JOIN
tableName b
ON
a.week-1=b.week

Answer 3

放手一搏：

SELECT VAR(hips) AS hips, VAR(wrist) AS wrist,
       VAR(abs) AS abs, VAR(weight) AS weight
FROM measurements
WHERE week IN (1,2)

Answer 4

如果出于某种原因，周数不合适，您也可以使用它：

;With Data As
(
    Select  hips, wrist, [abs], [weight],
            Row_Number() Over (Order By Week) RN
    From    Measurements
)
Select  Cur.Hips - Prev.Hips            As Hips,
        Cur.Wrist - Prev.Wrist          As Wrist,
        Cur.[Abs] - Prev.[Abs]          As [Abs],
        Cur.[Weight] - Prev.[Weight]    As [Weight]
From    Data Prev
Join    Data Cur On Cur.RN = Prev.RN + 1

如何从同一个表sql中减去

4 个答案: