Question

我有以下mysql数据库表：

cities

states

countries

带

members

samajs（一群国际人士）

我想为我的dashboard页面创建一个查询，其中包含以下结果：

Country   Members Samajs Total   (table header)

Country1    7      5     16      (country row with total members, samajs and total count)

  state1    5      2     7       (state row with total members, samajs and total count)

    city1   3      1     4       (all cities in that state, city row with total members, samajs and total count)

    city2   2      0     2         

  state2    2      1     3

Country2    3      2     5      (country row with total members, samajs and total count)

 ...and vice versa....

此处，members表将country_id, state_id and city_id作为外键

samajs表也将country_id, state_id and city_id作为外键

任何想法，将会查询什么？

谢谢！

Answer 1

最后，制作了一个查询，在union和subqueries的帮助下，按照预期为我提供了结果，如下所示：

SELECT country_id, state_id, city_id, country, membercount, samajcount FROM
        (

        SELECT con.country_id, -1 as state_id, -2 as city_id, con.country, 
        (SELECT COUNT(member_id) FROM members WHERE country_id = con.country_id) as membercount, 
        (SELECT COUNT(samaj_id) FROM samajs WHERE country_id = con.country_id) as samajcount
        FROM countries as con
        group by con.country  

        UNION 

        SELECT s.country_id, s.state_id, -2 as city_id, s.state as country, 
        (SELECT COUNT(member_id) FROM members WHERE state_id = s.state_id) as membercount, 
        (SELECT COUNT(samaj_id) FROM samajs WHERE state_id = s.state_id) as samajcount
        FROM states as s
        group by s.state  

        UNION

        SELECT c.country_id, c.state_id, c.city_id, c.city as country, 
        (SELECT COUNT(member_id) FROM members WHERE city_id = c.city_id) as membercount, 
        (SELECT COUNT(samaj_id) FROM samajs WHERE city_id = c.city_id) as samajcount
        FROM cities as c
        group by c.city  

        ) COUNTRY  

        order by country_id, state_id, city_id, country ;

希望能帮助某人满足他们的要求!!

谢谢

Answer 2

我已根据您的表字段准备了一个查询更改：

// for country based 
SELECT  
countries.name AS countryName,
(SELECT
count('x') FROM members WHERE members.country_id = countries.id) as totalMembers,
COUNT(samajs.country_id) as totalSamajs
FROM 
    `countries`
INNER JOIN samajs ON samajs.country_id = countries.id
GROUP BY 
    countries.name
ORDER BY
   totalMembers DESC

// state based result

    SELECT  
states.name AS stateName,
(SELECT
count('x') FROM members WHERE members.state_id = states.id) as totalMembers,
COUNT(samajs.state_id) as totalSamajs
FROM 
    `states`
INNER JOIN samajs ON samajs.state_id = states.id
GROUP BY 
    states.name
ORDER BY
   totalMembers DESC

//city based result

SELECT  
cities.name AS cityName,
(SELECT
count('x') FROM members WHERE members.city_id = cities.id) as totalMembers,
COUNT(samajs.city_id) as totalSamajs
FROM 
    `cities`
INNER JOIN samajs ON samajs.city_id = cities.id
GROUP BY 
    cities.name
ORDER BY
   totalMembers DESC

按照cakephp方法你可以按照这个问题：
Order data based on count of related table data

cakephp / php用于仪表板统计信息的Mysql复杂查询

2 个答案: