Mysql 插入select查询需要10分钟以上

几周前我运行一个不到1分钟的查询，现在已经用了10分钟，看不到尽头

新查询（需要很长时间）

查询：

INSERT INTO school_data_race_ethnicity_schools (school_id, year, race, percent) (
    SELECT school_id,
           year,
           race,
           ROUND((count/(
        SELECT SUM(count) 
          FROM school_data_race_ethnicity_raw as school_data_race_ethnicity_raw_inner 
         WHERE school_id = school_data_race_ethnicity_raw_outer.school_id 
           and year = school_data_race_ethnicity_raw_outer.year)
                        ) * 100,2) as percent
      FROM school_data_race_ethnicity_raw as school_data_race_ethnicity_raw_outer)    

说明：

mysql> explain SELECT school_id,year,race,ROUND((count/(SELECT SUM(count) 
    -> FROM school_data_race_ethnicity_raw as school_data_race_ethnicity_raw_inner 
    -> WHERE 
    -> school_id = school_data_race_ethnicity_raw_outer.school_id and 
    -> year = school_data_race_ethnicity_raw_outer.year)) * 100,2) as percent
    -> FROM school_data_race_ethnicity_raw as school_data_race_ethnicity_raw_outer;
+----+--------------------+--------------------------------------+------+----------------------------+------+---------+-----------------------------------------------------------------+-------+-------------+
| id | select_type        | table                                | type | possible_keys              | key  | key_len | ref                                                             | rows  | Extra       |
+----+--------------------+--------------------------------------+------+----------------------------+------+---------+-----------------------------------------------------------------+-------+-------------+
|  1 | PRIMARY            | school_data_race_ethnicity_raw_outer | ALL  | NULL                       | NULL | NULL    | NULL                                                            | 84012 |             |
|  2 | DEPENDENT SUBQUERY | school_data_race_ethnicity_raw_inner | ref  | school_id,year,school_id_2 | year | 4       | rocdocs_main_drupal_7.school_data_race_ethnicity_raw_outer.year |  8402 | Using where |
+----+--------------------+--------------------------------------+------+----------------------------+------+---------+-----------------------------------------------------------------+-------+-------------+
2 rows in set (0.00 sec)

创建表：

mysql> show create table school_data_race_ethnicity_raw;
+--------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table                          | Create Table                                                                                                                                                                                                                                                                                                                                                                                                  |
+--------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| school_data_race_ethnicity_raw | CREATE TABLE `school_data_race_ethnicity_raw` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `school_id` varchar(255) NOT NULL,
  `year` int(11) NOT NULL,
  `race` varchar(255) NOT NULL,
  `count` int(11) NOT NULL,
  PRIMARY KEY (`id`),
  KEY `school_id` (`school_id`,`year`),
  KEY `year` (`year`,`race`),
  KEY `school_id_2` (`school_id`)
) ENGINE=MyISAM AUTO_INCREMENT=84013 DEFAULT CHARSET=latin1 |
+--------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

mysql> show create table school_data_race_ethnicity_schools;
+------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table                              | Create Table                                                                                                                                                                                                                                                                                                                                                                           |
+------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| school_data_race_ethnicity_schools | CREATE TABLE `school_data_race_ethnicity_schools` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `school_id` varchar(255) NOT NULL,
  `year` int(11) NOT NULL,
  `race` varchar(255) NOT NULL,
  `percent` decimal(15,2) NOT NULL,
  PRIMARY KEY (`id`),
  KEY `year` (`year`,`race`),
  KEY `school_id` (`school_id`,`year`)
) ENGINE=MyISAM AUTO_INCREMENT=24961 DEFAULT CHARSET=latin1 |
+------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)


mysql> show processlist;
+------+---------+--------------------+-----------------------+---------+------+--------------+------------------------------------------------------------------------------------------------------+
| Id   | User    | Host               | db                    | Command | Time | State        | Info                                                                                                 |
+------+---------+--------------------+-----------------------+---------+------+--------------+------------------------------------------------------------------------------------------------------+
| 1739 | [REMOVED] |  [REMOVED] | rocdocs_main_drupal_7 | Query   | 1467 | Sending data | INSERT INTO school_data_race_ethnicity_schools (school_id, year, race, percent) (
SELECT school_id,y |
| 1800 | root    | localhost          | rocdocs_main_drupal_7 | Query   |    0 | NULL         | show processlist                                                                                     |
+------+---------+--------------------+-----------------------+---------+------+--------------+------------------------------------------------------------------------------------------------------+
2 rows in set (0.00 sec)

---

由于使用子查询来计算百分比的方式，您的选择将非常缓慢。它读取每行一整年的数据。如果您使用子查询来选择总计并加入其中，那么它应该运行得更快

在我看来，类似这样的查询（虽然不理想）应该比您现有的查询快得多：

select detail.school_id, 
  detail.year, 
  detail.race,
  ROUND((detail.count / summary.total) * 100 ,2) as percent 
FROM school_data_race_ethnicity_raw as detail
inner join (
  select school_id, year, sum(count) as total
  from school_data_race_ethnicity_raw
  group by school_id, year
  ) as summary on summary.school_id = detail.school_id 
    and summary.year = detail.year

---

让我们处理

SELECT

查询。让我们一件一件地做。看起来您希望每个不同的学校、种族和年份都有一排。这很简单

   SELECT r.school_id, r.year, r.race, something
     FROM school_data_race_ethnicity_raw r
    GROUP BY r.school_id, r.year, r.race

现在让我们整理一下你的

指标。很难从你的问题中准确地说出来，但我会猜。看起来你想要的是每个种族学生的分数

因此，我们需要处理两个摘要查询。一个是每年每个学校的学生总数

  SELECT r.school_id, r.year, SUM(count) count
    FROM school_data_race_ethnicity_raw r
GROUP BY r.school_id, r.year

第二个是按学校、年份和种族列出的学生总数

  SELECT r.school_id, r.year, r.race, SUM(count) count
    FROM school_data_race_ethnicity_raw r
GROUP BY r.school_id, r.year, r.race

然后，我们需要将这两个查询连接在一起，就像它们是虚拟表一样，这样我们就可以执行以下操作：

  SELECT t.school_id, t.year, u.race, u.count/t.count percent
     FROM 
     (
          SELECT r.school_id, r.year, SUM(count) count
            FROM school_data_race_ethnicity_raw r
        GROUP BY r.school_id, r.year
     ) t
     LEFT JOIN
     (
          SELECT r.school_id, r.year, r.race, SUM(count) count
            FROM school_data_race_ethnicity_raw r
        GROUP BY r.school_id, r.year, r.race
     ) u ON (t.school_id = u.school_id AND t.year = u.year)

最后，您需要百分比，所以让我们将分数乘以100.0

   SELECT t.school_id, t.year, u.race, ROUND(100.0*u.count/t.count, 2) percent
     FROM 
     (
          SELECT r.school_id, r.year, SUM(count) count
            FROM school_data_race_ethnicity_raw r
        GROUP BY r.school_id, r.year
     ) t
     LEFT JOIN
     (
          SELECT r.school_id, r.year, r.race, SUM(count) count
            FROM school_data_race_ethnicity_raw r
        GROUP BY r.school_id, r.year, r.race
     ) u ON (t.school_id = u.school_id AND t.year = u.year)

您的进程被阻止了吗？是否有任何打开的事务导致此进程等待？我将进程列表置于问题中。它似乎没有被阻止，因为它是唯一正在运行的查询。
ROUND（（detail.count/summary.total）*100，2）as percent
您能看看我在原始问题中发布的相关查询吗？我试着按地区分组，我试着使用相同的模式，但速度真的很慢。
   SELECT t.school_id, t.year, u.race, ROUND(100.0*u.count/t.count, 2) percent
     FROM 
     (
          SELECT r.school_id, r.year, SUM(count) count
            FROM school_data_race_ethnicity_raw r
        GROUP BY r.school_id, r.year
     ) t
     LEFT JOIN
     (
          SELECT r.school_id, r.year, r.race, SUM(count) count
            FROM school_data_race_ethnicity_raw r
        GROUP BY r.school_id, r.year, r.race
     ) u ON (t.school_id = u.school_id AND t.year = u.year)