我需要将2700万行表中的信息与700万行表中的信息结合起来,并进行一些过滤。

CREATE TABLE event_participation (
    place_id                    int(4),
    person_id                   varchar(12),
    event_id                    varchar(10),
    event_description           varchar(230),

    .... and more fields about that specific participation

) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE INDEX IDX_1 ON event_participation (place_id);
CREATE INDEX IDX_2 ON event_participation (person_id);
CREATE INDEX IDX_3 ON event_participation (event_id);

CREATE TABLE person (
    person_id                   varchar(12),
    last_name                   varchar(25),
    first_name                  varchar(20),
    middle_name                 varchar(20),

    person_attr1                varchar(20),
    ...
    person_attr50              varchar(20),

) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE INDEX IDX_10 ON person (person_id);
CREATE INDEX IDX_11 ON person (person_attr1);
CREATE INDEX IDX_12 ON person (person_attr2);
...


我对查询中使用的所有属性都有索引。

event_participation表中有2700万行,表person中有700万行。

我需要运行这样的查询:

SELECT   person.last_name, person.first_name
FROM     event_participation
    LEFT JOIN person ON event_participation.person_id = person.person_id
WHERE    event_id IN ("event 1", "event 2", "event 3", "event 4",
         "event 5", "event 6", "event 7") AND person.person_attr1 = 'A' AND
         person.person_attr2 = 'B' AND place_id = 90
GROUP BY event_participation.person_id
HAVING   count(event_id) >= 3


解释是:

*************************** 1. row ***************************
           id: 1
  select_type: SIMPLE
        table: event_participation
         type: ref
possible_keys: person_id,event_id,place_id
          key: place_id
      key_len: 5
          ref: const
         rows: 6437170
        Extra: Using where; Using temporary; Using filesort
*************************** 2. row ***************************
           id: 1
  select_type: SIMPLE
        table: person
         type: ref
possible_keys: person_id,person_attr1,person_attr2
          key: person_id
      key_len: 39
          ref: event_participation.person_id
         rows: 1
        Extra: Using where


我正在寻找参加活动的人,这些人至少要参加列表中的3个活动,并且还满足其他一些条件。通常,我会修复与事件相关的条件,并运行多个仅更改人员属性的查询。

即使对于很小的子集,此查询也非常慢,因此我寻找替代方法。
我创建一个缓存表:

CREATE TABLE temp_name (
    person_id                   varchar(12),
    PRIMARY KEY (person_id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;


运行如下查询:

INSERT INTO temp_name (  temp_name )
    SELECT   DISTINCT event_participation.person_id
    FROM     event_participation
    WHERE    event_id IN ("event 1", "event 2", "event 3", "event 4",
             "event 5", "event 6", "event 7") AND place_id = 90
    GROUP BY event_participation.person_id
    HAVING   count(event_id) >= 3


然后运行过滤器查询,如:

SELECT person.last_name, person.first_name
FROM temp_name LEFT JOIN person ON temp_name.person_id = person.person_id
WHERE person.person_attr1 = 'A' AND person.person_attr2 = 'B'


虽然我可以保留最终查询的当前性能,但是创建和管理临时表却使我丧命。任何建议将不胜感激。

最佳答案

您可以尝试一下:

SELECT   person.last_name, person.first_name
FROM person pers
INNER JOIN
(SELECT person_id, count(*) as count
FROM     event_participation
WHERE    event_id IN ("event 1", "event 2", "event 3", "event 4",
         "event 5", "event 6", "event 7") AND person.person_attr1 = 'A' AND
         person.person_attr1 = 'B' AND place_id = 90
Group by person_id
) as event_count on event_count.person_id = pers.person_id AND event_count.count>2


更新:我忘记将分组依据添加到内部查询中。

10-08 07:35
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