計算累計與移動平均

SQL Server 的時間序列分析

Maham Faisal Khan

Senior Data Science Content Developer

計算累計

Team	Game	RunsScored
AZ	1	8
AZ	2	6
AZ	3	3
FLA	1	7
FLA	2	7
FLA	3	6

Team	Game	RunsScored	TotalRuns
AZ	1	8	8
AZ	2	6	14
AZ	3	3	17
FLA	1	7	7
FLA	2	7	14
FLA	3	6	20

累計（Running totals）

SELECT
    s.Team,
    s.Game,
    s.RunsScored,
    SUM(s.RunsScored) OVER (
        PARTITION BY s.Team
        ORDER BY s.Game ASC
        RANGE BETWEEN
              UNBOUNDED PRECEDING
              AND CURRENT ROW
    ) AS TotalRuns
FROM #Scores s;

Team、Game、RunsScored 欄位
SUM(s.RunsScored)
OVER()
PARTITION BY s.Team
ORDER BY s.Game ASC
RANGE BETWEEN
UNBOUNDED PRECEDING
AND CURRENT ROW

RANGE 與 ROWS

`RANGE`

指定結果範圍
「重複值」一次處理完
只支援 UNBOUNDED 與 CURRENT ROW

`ROWS`

指定要包含的列數
「重複值」逐列處理
支援 UNBOUNDED、CURRENT ROW，以及指定列數

計算移動平均

SELECT
    s.Team,
    s.Game,
    s.RunsScored,
    AVG(s.RunsScored) OVER (
        PARTITION BY s.Team
        ORDER BY s.Game ASC
        ROWS BETWEEN 1 PRECEDING
            AND CURRENT ROW
    ) AS AvgRuns
FROM #Scores s;

Team	Game	RunsScored	AvgRuns
AZ	1	8	8
AZ	2	6	7
AZ	3	3	4
FLA	1	7	7
FLA	2	7	7
FLA	3	6	6

一起來練習吧！

SQL Server 的時間序列分析