mysql - 需要帮助使用在两个单独表的列之间进行算术运算的函数将列添加到一个表

我正在尝试使用 sequel-pro 将列“wOBA”添加到 MySQL 中的表“starting_pitcher_stats”。以下是对“starting_pitcher_stats”表中的九个变量执行算术运算的函数代码。特别是，该函数收集多个变量的值，对其中一些变量(下面的分子)应用不同的权重(系数)，并将该总和除以更多变量的加法和减法。所有这些变量都位于“starting_pitcher_stats”表中。算术运算用以下公式表示(系数是与下面分子中的每个变量相乘的值):

wOBA=(.69*walks_a + .72*HBP + .89*singles_a + 1.27*doubles_a + 1.62*triples_a+ 2.10*HR_a)/(at_bats+walks_a+SF+HBP)

每个权重因年份而异。每年的不同权重来自“GUTS”表。

我遇到的第一个难题是获取函数的正确代码。第二个是用于实际调用此函数的正确代码语法，并为每个“Starting_Pitcher”的每年(赛季)的每场比赛使用正确的加权 wOBA 值填充新列。

该函数是用下面的代码创建的，在我的函数和过程列表中列为函数“wOBA”。但是，由于某种原因，sequel pro 中功能名称旁边的小轮/旋钮是灰色的。直到我找到调用它的正确代码，我才会知道是否有任何错误。

请询问我可以提供的任何更多信息以澄清任何问题。

提前谢谢你。

DELIMITER $$
    CREATE FUNCTION wOBA(wOBA DECIMAL(10,3))
    RETURNS DECIMAL(10,3)
    BEGIN
        DECLARE wOBA decimal(10,3);
        SET wOBA = 0;
        SELECT cast((SELECT SUM(weighted_BB) as wBB_sum 
            FROM (
                SELECT g.wBB*SUM(if(e.event_CD=14,1,0)) as weighted_BB 
                FROM events e 
                INNER JOIN GUTS g 
                    ON substring(e.game_ID,4,4)=g.season 
                WHERE PIT_ID=Starting_Pitcher 
                GROUP BY g.season) 
            as walks_a)  
            + (SELECT SUM(weighted_HBP) as wHBP_sum 
            FROM (
                SELECT g.wHBP*SUM(if(e.event_CD=16,1,0)) as weighted_HBP 
                FROM events e 
                INNER JOIN GUTS g 
                    ON substring(e.game_ID,4,4)=g.season 
                WHERE PIT_ID=Starting_Pitcher 
                GROUP BY g.season) 
            as HBP)     
            + (SELECT SUM(weighted_1B) as w1B_sum 
            FROM (
                SELECT g.w1B*SUM(if(e.event_CD=20,1,0)) as weighted_1B 
                FROM events e 
                INNER JOIN GUTS g 
                    ON substring(e.game_ID,4,4)=g.season 
                WHERE PIT_ID=Starting_Pitcher 
                GROUP BY g.season) 
            as singles_a)       
            + (SELECT SUM(weighted_2B) as w2B_sum 
            FROM ( 
                SELECT g.w2B*SUM(if(e.event_CD=21,1,0)) as weighted_2B 
                FROM events e 
                INNER JOIN GUTS g 
                    ON substring(e.game_ID,4,4)=g.season 
                WHERE PIT_ID=Starting_Pitcher 
                GROUP BY g.season) 
            as doubles_a)       
            + (SELECT SUM(weighted_3B) as w3B_sum 
            FROM (
                SELECT g.w3B*SUM(if(e.event_CD=22,1,0)) as weighted_3B 
                FROM events e 
                INNER JOIN GUTS g 
                    ON substring(e.game_ID,4,4)=g.season 
                WHERE PIT_ID=Starting_Pitcher 
                GROUP BY g.season) 
            as triples_a)       
            + (SELECT SUM(weighted_HR) as wHR_sum 
            FROM (
                SELECT g.wHR*SUM(if(e.event_CD=23,1,0)) as weighted_HR 
                FROM events e 
                INNER JOIN GUTS g 
                    ON substring(e.game_ID,4,4)=g.season 
                WHERE PIT_ID=Starting_Pitcher 
                GROUP BY g.season) 
            as HR_a) as decimal(10,3))
            /
            cast(SUM(if(e.ab_fl="T",1,0)) 
                + SUM(if(e.event_cd=14,1,0)) 
                + SUM(if(e.SF_fl="T",1,0)) 
                + SUM(if(e.event_cd=16,1,0)) as unsigned) INTO wOBA 
            FROM events e
            WHERE e.PIT_ID=Starting_Pitcher AND PIT_START_FL = "T"
            LIMIT 1;
        RETURN wOBA;
    END
    $$
    DELIMITER ;

Darwin，这是 events 表的两个屏幕截图。第一个是结构，第二个是一些内容(因为并非所有内容都适合镜头):

[ structure of events table[1]

以下是 GUTS 表的结构和内容的屏幕截图。

这是事件表结构的屏幕截图，显示了函数中的字段(及其定义):

更新:

UPDATE retrosheet.starting_pitcher_stats 
SET starting_pitcher_stats.wOBA =(SELECT
(
   (g.wBB * SUM(IF(e.event_cd = 14, 1, 0)))
   + (g.wHBP * SUM(IF(e.event_cd = 16, 1, 0)))
   + (g.w1B  * SUM(IF(e.event_cd = 20, 1, 0)))
   + (g.w2B  * SUM(IF(e.event_cd = 21, 1, 0)))
   + (g.w3B  * SUM(IF(e.event_cd = 22, 1, 0)))
   + (g.wHR  * SUM(IF(e.event_cd = 23, 1, 0)))
   )
   /
   (
     SUM(IF(e.ab_fl = 'T',   1, 0))
   + SUM(IF(e.event_cd = 14, 1, 0))
   + SUM(IF(e.sf_fl = 'T',   1, 0))
   + SUM(IF(e.event_cd = 16, 1, 0))
  ) AS wOBA
  FROM events AS e, GUTS AS g
  WHERE e.YEAR_ID = g.SEASON_ID
    AND e.PIT_START_FL= 'T'
    AND e.PIT_ID = Starting_Pitcher)

查询一直在运行。我会继续调整它。

更新: starting_pitcher_stats 表的屏幕截图

更新:

好的，我正在尝试创建一个 wOBA 列作为新表的一部分，其中包含 wOBA 其他组件的列。

但是，查询会一直持续下去。如何缩短运行时间？

DROP TABLE IF EXISTS starting_pitcher_wOBA;
CREATE TABLE starting_pitcher_wOBA 
SELECT
a.YEAR_ID
,
a.GAME_ID
,
a.PIT_ID
,
a.wBB
,
a.wHBP
,
a.w1B
,
a.w2B
,
a.w3B
,
a.wHR
,
a.u_walks_a
,
a.HBP
,
a.singles_a
,
a.doubles_a
,
a.triples_a
,
a.HR_a
,
a.at_bats
,
a.sacrifice_flies_a
,
a.wOBA
FROM
(
SELECT 
g.YEAR_ID
,
h.GAME_ID
,
e.PIT_ID
,
g.wBB
,
g.wHBP
,
g.w1B
,
g.w2B
,
g.w3B
,
g.wHR
,
SUM(IF(e.event_cd = 14, 1, 0)) AS u_walks_a
,
SUM(IF(e.event_cd = 16, 1, 0)) AS HBP
,
SUM(IF(e.event_cd = 20, 1, 0)) AS singles_a
,
SUM(IF(e.event_cd = 21, 1, 0)) AS doubles_a
,
SUM(IF(e.event_cd = 22, 1, 0)) AS triples_a
,
SUM(IF(e.event_cd = 23, 1, 0)) AS HR_a
,
SUM(IF(e.ab_fl = 'T',   1, 0)) AS at_bats
,
SUM(IF(e.sf_fl = 'T',   1, 0)) AS sacrifice_flies_a
,
(
(
   (g.wBB * SUM(IF(e.event_cd = 14, 1, 0))) 
   + (g.wHBP * SUM(IF(e.event_cd = 16, 1, 0))) 
   + (g.w1B  * SUM(IF(e.event_cd = 20, 1, 0))) 
   + (g.w2B  * SUM(IF(e.event_cd = 21, 1, 0))) 
   + (g.w3B  * SUM(IF(e.event_cd = 22, 1, 0))) 
   + (g.wHR  * SUM(IF(e.event_cd = 23, 1, 0))) 
   )
   /
   (
     SUM(IF(e.ab_fl = 'T',   1, 0)) 
   + SUM(IF(e.event_cd = 14, 1, 0)) 
   + SUM(IF(e.sf_fl = 'T',   1, 0)) 
   + SUM(IF(e.event_cd = 16, 1, 0)) 
  ) 
 )  AS wOBA
FROM events AS e, GUTS AS g, game AS h
WHERE e.PIT_START_FL= 'T' 
GROUP BY g.YEAR_ID, h.GAME_ID,e.PIT_ID) AS a
INNER JOIN GUTS AS g
ON 
a.YEAR_ID=g.YEAR_ID
INNER JOIN game AS h
ON
a.GAME_ID = h.GAME_ID
INNER JOIN events AS e
ON
a.PIT_ID = e.PIT_ID

最佳答案

我们将从清理查询开始。您应该尽可能尝试对每一行执行计算，而不是执行多个垂直子查询，因为这样可以避免 DBMS 对同一个表进行多次传递。

SELECT
  (
   ( (g.wbb  * SUM(IF(e.event_cd = 14, 1, 0)))
   + (g.whbp * SUM(IF(e.event_cd = 16, 1, 0)))
   + (g.w1b  * SUM(IF(e.event_cd = 20, 1, 0)))
   + (g.w2b  * SUM(IF(e.event_cd = 21, 1, 0)))
   + (g.w3b  * SUM(IF(e.event_cd = 22, 1, 0)))
   + (g.whr  * SUM(IF(e.event_cd = 23, 1, 0)))
   )
   /
   (
     SUM(IF(e.ab_fl = 'T',   1, 0))
   + SUM(IF(e.event_cd = 14, 1, 0))
   + SUM(IF(e.sf_fl = 'T',   1, 0))
   + SUM(IF(e.event_cd = 16, 1, 0))
   )
  ) AS woba
  FROM events e, guts g
  WHERE e.year_id = g.season_id
    AND e.pit_start_fl = 'T'
    AND e.pit_id = starting_pitcher
  GROUP BY g.season;

假设我没有在某处留下逗号，这将为指定的首发投手每年返回一列 woba。

请注意，我在 e.year_id 而不是 SUBSTRING(e.game_ID,4,4) 上加入了表格；这避免了在每条记录上调用 SUBSTRING() 的开销。这种事情看起来微不足道，但在一张大 table 上会很快累积起来。

这应该足以让您入门。

关于mysql - 需要帮助使用在两个单独表的列之间进行算术运算的函数将列添加到一个表，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/34538685/

mysql - 需要帮助使用在两个单独表的列之间进行算术运算的函数将列添加到一个表

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