累積合計と移動平均の計算

SQL Serverで学ぶ時系列分析

Maham Faisal Khan

Senior Data Science Content Developer

累積合計の計算

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

累積合計（Running total）

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

RANGE と ROWS

`RANGE`

結果の範囲を指定
「重複」を一度に処理
UNBOUNDED と CURRENT ROW のみ対応

`ROWS`

含める行数を指定
「重複」を1行ずつ処理
UNBOUNDED、CURRENT ROW、行数に対応

移動平均の計算

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

演習に進みましょう！

SQL Serverで学ぶ時系列分析