目标：按地区显示每个种族和年份的种族数据占总数的百分比。
问题：查询需要30多分钟才能运行。我想把它降到10秒以下。还有另一种解决这个问题的策略是我没想到的吗？
查询：
SELECT field_data_field_district_id.field_district_id_value as district_id, year, race, ROUND(SUM(count)/(
SELECT SUM(count)
FROM school_data_race_ethnicity_raw as school_data_race_ethnicity_raw_inner
INNER JOIN field_data_field_school_id as field_data_field_school_id_inner ON field_data_field_school_id_inner.field_school_id_value = school_data_race_ethnicity_raw_inner.school_id
INNER JOIN field_data_field_district as field_data_field_district_inner ON field_data_field_district_inner.entity_id = field_data_field_school_id_inner.entity_id
INNER JOIN field_data_field_district_id as field_data_field_district_id_inner ON field_data_field_district_inner.field_district_nid = field_data_field_district_id_inner.entity_id
WHERE field_data_field_district_id_inner.field_district_id_value = field_data_field_district_id.field_district_id_value and
school_data_race_ethnicity_raw_inner.year = school_data_race_ethnicity_raw.year
) * 100 ,2) as percent
FROM school_data_race_ethnicity_raw
INNER JOIN field_data_field_school_id ON field_data_field_school_id.field_school_id_value = school_data_race_ethnicity_raw.school_id
INNER JOIN field_data_field_district ON field_data_field_district.entity_id = field_data_field_school_id.entity_id
INNER JOIN field_data_field_district_id ON field_data_field_district.field_district_nid = field_data_field_district_id.entity_id
GROUP BY district_id, year, race
说明：
+----+--------------------+--------------------------------------+------+------------------------------+--------------------+---------+--------------------------------------------------------------------+-------+---------------------------------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+--------------------+--------------------------------------+------+------------------------------+--------------------+---------+--------------------------------------------------------------------+-------+---------------------------------+
| 1 | PRIMARY | field_data_field_district_id | ALL | entity_id | NULL | NULL | NULL | 685 | Using temporary; Using filesort |
| 1 | PRIMARY | field_data_field_district | ref | entity_id,field_district_nid | field_district_nid | 5 | rocdocs_main_drupal_7.field_data_field_district_id.entity_id | 3 | Using where; Using index |
| 1 | PRIMARY | field_data_field_school_id | ref | entity_id | entity_id | 4 | rocdocs_main_drupal_7.field_data_field_district.entity_id | 1 | |
| 1 | PRIMARY | school_data_race_ethnicity_raw | ALL | NULL | NULL | NULL | NULL | 97098 | Using where; Using join buffer |
| 2 | DEPENDENT SUBQUERY | field_data_field_district_id_inner | ALL | entity_id | NULL | NULL | NULL | 685 | Using where |
| 2 | DEPENDENT SUBQUERY | field_data_field_district_inner | ref | entity_id,field_district_nid | field_district_nid | 5 | rocdocs_main_drupal_7.field_data_field_district_id_inner.entity_id | 3 | Using where; Using index |
| 2 | DEPENDENT SUBQUERY | field_data_field_school_id_inner | ref | entity_id | entity_id | 4 | rocdocs_main_drupal_7.field_data_field_district_inner.entity_id | 1 | |
| 2 | DEPENDENT SUBQUERY | school_data_race_ethnicity_raw_inner | ref | year | year | 4 | func | 32366 | Using where |
+----+--------------------+--------------------------------------+------+------------------------------+--------------------+---------+--------------------------------------------------------------------+-------+---------------------------------+
表：
school_data_race_ethnicity_raw - （约100,000行）
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=97099 DEFAULT CHARSET=latin1 |
+--------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)
field_data_field_school_id - 约。 5000行
mysql> show create table field_data_field_school_id;
+----------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table | Create Table |
+----------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| field_data_field_school_id | CREATE TABLE `field_data_field_school_id` (
`entity_type` varchar(128) NOT NULL DEFAULT '' COMMENT 'The entity type this data is attached to',
`bundle` varchar(128) NOT NULL DEFAULT '' COMMENT 'The field instance bundle to which this row belongs, used when deleting a field instance',
`deleted` tinyint(4) NOT NULL DEFAULT '0' COMMENT 'A boolean indicating whether this data item has been deleted',
`entity_id` int(10) unsigned NOT NULL COMMENT 'The entity id this data is attached to',
`revision_id` int(10) unsigned DEFAULT NULL COMMENT 'The entity revision id this data is attached to, or NULL if the entity type is not versioned',
`language` varchar(32) NOT NULL DEFAULT '' COMMENT 'The language for this data item.',
`delta` int(10) unsigned NOT NULL COMMENT 'The sequence number for this data item, used for multi-value fields',
`field_school_id_value` varchar(255) DEFAULT NULL,
`field_school_id_format` varchar(255) DEFAULT NULL,
PRIMARY KEY (`entity_type`,`entity_id`,`deleted`,`delta`,`language`),
KEY `entity_type` (`entity_type`),
KEY `bundle` (`bundle`),
KEY `deleted` (`deleted`),
KEY `entity_id` (`entity_id`),
KEY `revision_id` (`revision_id`),
KEY `language` (`language`),
KEY `field_school_id_format` (`field_school_id_format`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COMMENT='Data storage for field 234 (field_school_id)' |
+----------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)
field_data_field_district - 约。 5000行
mysql> show create table field_data_field_district;
+---------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table | Create Table |
+---------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| field_data_field_district | CREATE TABLE `field_data_field_district` (
`entity_type` varchar(128) NOT NULL DEFAULT '' COMMENT 'The entity type this data is attached to',
`bundle` varchar(128) NOT NULL DEFAULT '' COMMENT 'The field instance bundle to which this row belongs, used when deleting a field instance',
`deleted` tinyint(4) NOT NULL DEFAULT '0' COMMENT 'A boolean indicating whether this data item has been deleted',
`entity_id` int(10) unsigned NOT NULL COMMENT 'The entity id this data is attached to',
`revision_id` int(10) unsigned DEFAULT NULL COMMENT 'The entity revision id this data is attached to, or NULL if the entity type is not versioned',
`language` varchar(32) NOT NULL DEFAULT '' COMMENT 'The language for this data item.',
`delta` int(10) unsigned NOT NULL COMMENT 'The sequence number for this data item, used for multi-value fields',
`field_district_nid` int(10) unsigned DEFAULT NULL,
PRIMARY KEY (`entity_type`,`entity_id`,`deleted`,`delta`,`language`),
KEY `entity_type` (`entity_type`),
KEY `bundle` (`bundle`),
KEY `deleted` (`deleted`),
KEY `entity_id` (`entity_id`),
KEY `revision_id` (`revision_id`),
KEY `language` (`language`),
KEY `field_district_nid` (`field_district_nid`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COMMENT='Data storage for field 221 (field_district)' |
+---------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)
field_data_field_district_id - 约：1000行
mysql> show create table field_data_field_district_id;
+------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table | Create Table |
+------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| field_data_field_district_id | CREATE TABLE `field_data_field_district_id` (
`entity_type` varchar(128) NOT NULL DEFAULT '' COMMENT 'The entity type this data is attached to',
`bundle` varchar(128) NOT NULL DEFAULT '' COMMENT 'The field instance bundle to which this row belongs, used when deleting a field instance',
`deleted` tinyint(4) NOT NULL DEFAULT '0' COMMENT 'A boolean indicating whether this data item has been deleted',
`entity_id` int(10) unsigned NOT NULL COMMENT 'The entity id this data is attached to',
`revision_id` int(10) unsigned DEFAULT NULL COMMENT 'The entity revision id this data is attached to, or NULL if the entity type is not versioned',
`language` varchar(32) NOT NULL DEFAULT '' COMMENT 'The language for this data item.',
`delta` int(10) unsigned NOT NULL COMMENT 'The sequence number for this data item, used for multi-value fields',
`field_district_id_value` varchar(255) DEFAULT NULL,
`field_district_id_format` varchar(255) DEFAULT NULL,
PRIMARY KEY (`entity_type`,`entity_id`,`deleted`,`delta`,`language`),
KEY `entity_type` (`entity_type`),
KEY `bundle` (`bundle`),
KEY `deleted` (`deleted`),
KEY `entity_id` (`entity_id`),
KEY `revision_id` (`revision_id`),
KEY `language` (`language`),
KEY `field_district_id_format` (`field_district_id_format`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COMMENT='Data storage for field 218 (field_district_id)' |
+------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
注意：我可以更改的唯一表是school_data_race_ethnicity_raw，其他表是由drupal生成的。
mysql> explain SELECT field_data_field_district_id_inner.field_district_id_value,
-> school_data_race_ethnicity_raw_inner.year,
-> SUM(count) as total
-> FROM school_data_race_ethnicity_raw as school_data_race_ethnicity_raw_inner
-> INNER JOIN field_data_field_school_id as field_data_field_school_id_inner
-> ON field_data_field_school_id_inner.field_school_id_value
-> = school_data_race_ethnicity_raw_inner.school_id
-> INNER JOIN field_data_field_district as field_data_field_district_inner
-> ON field_data_field_district_inner.entity_id
-> = field_data_field_school_id_inner.entity_id
-> INNER JOIN field_data_field_district_id as field_data_field_district_id_inner
-> ON field_data_field_district_inner.field_district_nid
-> = field_data_field_district_id_inner.entity_id
-> GROUP BY field_district_id_value, year
-> ;
+----+-------------+--------------------------------------+------+------------------------------+--------------------+---------+--------------------------------------------------------------------+-------+---------------------------------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+--------------------------------------+------+------------------------------+--------------------+---------+--------------------------------------------------------------------+-------+---------------------------------+
| 1 | SIMPLE | field_data_field_district_id_inner | ALL | entity_id | NULL | NULL | NULL | 773 | Using temporary; Using filesort |
| 1 | SIMPLE | field_data_field_district_inner | ref | entity_id,field_district_nid | field_district_nid | 5 | rocdocs_main_drupal_7.field_data_field_district_id_inner.entity_id | 3 | Using where; Using index |
| 1 | SIMPLE | field_data_field_school_id_inner | ref | entity_id | entity_id | 4 | rocdocs_main_drupal_7.field_data_field_district_inner.entity_id | 1 | |
| 1 | SIMPLE | school_data_race_ethnicity_raw_inner | ALL | NULL | NULL | NULL | NULL | 97098 | Using where; Using join buffer |
+----+-------------+--------------------------------------+------+------------------------------+--------------------+---------+--------------------------------------------------------------------+-------+---------------------------------+
4 rows in set (0.00 sec)
答案 0 :(得分：1)
这个怎么样：
SELECT field_data_field_district_id.field_district_id_value as district_id,
x.year,
race,
ROUND(SUM(count)/(x.total) * 100 , 2) as percent
FROM school_data_race_ethnicity_raw
INNER JOIN field_data_field_school_id
ON field_data_field_school_id.field_school_id_value
= school_data_race_ethnicity_raw.school_id
INNER JOIN field_data_field_district
ON field_data_field_district.entity_id
= field_data_field_school_id.entity_id
INNER JOIN field_data_field_district_id
ON field_data_field_district.field_district_nid
= field_data_field_district_id.entity_id
INNER JOIN (
SELECT field_data_field_district_id_inner.field_district_id_value,
school_data_race_ethnicity_raw_inner.year,
SUM(count) as total
FROM school_data_race_ethnicity_raw as school_data_race_ethnicity_raw_inner
INNER JOIN field_data_field_school_id as field_data_field_school_id_inner
ON field_data_field_school_id_inner.field_school_id_value
= school_data_race_ethnicity_raw_inner.school_id
INNER JOIN field_data_field_district as field_data_field_district_inner
ON field_data_field_district_inner.entity_id
= field_data_field_school_id_inner.entity_id
INNER JOIN field_data_field_district_id as field_data_field_district_id_inner
ON field_data_field_district_inner.field_district_nid
= field_data_field_district_id_inner.entity_id
GROUP BY field_district_id_value, year
) x ON x.field_district_id_value = field_data_field_district_id.field_district_id_value
AND x.year = school_data_race_ethnicity_raw.year
GROUP BY district_id, x.year, race
我基本上移动了你的查询，计算每个区/年的总数，从SELECT到另一个JOIN。
说明：
+----+-------------+--------------------------------------+------+------------------------------+--------------------+---------+--------------------------------------------------------------------+-------+---------------------------------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+--------------------------------------+------+------------------------------+--------------------+---------+--------------------------------------------------------------------+-------+---------------------------------+
| 1 | PRIMARY | field_data_field_district_id | ALL | entity_id | NULL | NULL | NULL | 773 | Using temporary; Using filesort |
| 1 | PRIMARY | field_data_field_district | ref | entity_id,field_district_nid | field_district_nid | 5 | rocdocs_main_drupal_7.field_data_field_district_id.entity_id | 3 | Using where; Using index |
| 1 | PRIMARY | field_data_field_school_id | ref | entity_id | entity_id | 4 | rocdocs_main_drupal_7.field_data_field_district.entity_id | 1 | |
| 1 | PRIMARY | <derived2> | ALL | NULL | NULL | NULL | NULL | 1902 | Using where; Using join buffer |
| 1 | PRIMARY | school_data_race_ethnicity_raw | ref | year | year | 4 | x.year | 32366 | Using where |
| 2 | DERIVED | field_data_field_district_id_inner | ALL | entity_id | NULL | NULL | NULL | 773 | Using temporary; Using filesort |
| 2 | DERIVED | field_data_field_district_inner | ref | entity_id,field_district_nid | field_district_nid | 5 | rocdocs_main_drupal_7.field_data_field_district_id_inner.entity_id | 3 | Using where; Using index |
| 2 | DERIVED | field_data_field_school_id_inner | ref | entity_id | entity_id | 4 | rocdocs_main_drupal_7.field_data_field_district_inner.entity_id | 1 | |
| 2 | DERIVED | school_data_race_ethnicity_raw_inner | ALL | NULL | NULL | NULL | NULL | 97098 | Using where; Using join buffer |
+----+-------------+--------------------------------------+------+------------------------------+--------------------+---------+--------------------------------------------------------------------+-------+---------------------------------+
9 rows in set (4 min 0.59 sec)