Question

我似乎正在努力获得每一行连续2天的股票价格之间的平均差异，并且会对此有所帮助。我相信使用内部联接可能有一种更简单的方法，但我真的很挣扎。

这是我的表


Symbol  Date    Price       Date        Price      Date     Price 
1250    2015-01-14  47.51   2015-01-13  48.30   2015-01-12  48.80

我正在尝试计算所有行的最近两天价格之间的平均百分比差异。我的表目前只有符号，日期和价格的数据，我想要的是

Symbol  Date    Price       % Change Date        Price     % Change  Date     Price 
1250    2015-01-14  47.51    -1.63    2015-01-13    48.30   2.02   2015-01-12   48.80

感谢您提供任何帮助或指导！

Answer 1

试试这个：

SELECT
    subQuery1.Symbol,
    subQuery1.Date AS 'Date 1',
    subQuery1.Price AS 'Price 1',
    ROUND(((subQuery1.Price - subQuery2.Price) / subQuery2.Price) * 100, 2) AS '% Change',
    subQuery2.Date AS 'Date 2',
    subQuery2.Price AS 'Price 2',
    ROUND(((subQuery2.Price - subQuery3.Price) / subQuery3.Price) * 100, 2) AS '% Change',
    subQuery3.Date AS 'Date 3',
    subQuery3.Price AS 'Price 3'
FROM
    (SELECT Symbol, Date, Price FROM tbl) AS subQuery1,
    (SELECT Symbol, Date, Price FROM tbl) AS subQuery2,
    (SELECT Symbol, Date, Price FROM tbl) AS subQuery3
WHERE
    subQuery1.Symbol = subQuery2.Symbol
    AND subQuery2.Symbol = subQuery3.Symbol
    AND subQuery1.Date = subQuery2.Date + INTERVAL 1 DAY
    AND subQuery2.Date = subQuery3.Date + INTERVAL 1 DAY

对于大型数据集，性能不会很好，因为它涉及三个子查询，临时表和没有索引......

如何查找每行最近2天的每日股票价格之间的平均差异

1 个答案: