我有以下2个SQL语句:
Select count(project.id) as '# Projects', c2.name as ' Country name' from project, country c2, project_country where project_country.project_id = project.id and project_country.country_id= c2.id group by c2.name;
select count(user.id) as '# Consultants',c1.name as ' Country name' from user,consultant_profile, country c1 where c1.id= user.country_id and user.is_active=1 and user.type=0 and user.id = consultant_profile.user_id group by country.name ;
是否可以根据country.id
字段组合这两个查询,因此我只有一个结果与#Projects,#Consultant和Country Name?
答案 0 :(得分:1)
您可以在其他表上的两个聚合查询中加入country
表:
SELECT c.name AS country_name, num_projects, num_consultants
FROM country c
JOIN (SELECT pc.country_id, COUNT(p.id) AS num_projects
FROM project p
JOIN project_country pc ON p.id = pc.projcet_id
GROUP BY pc.country_id) x ON x.country_id = c.id
JOIN (SELECT u.country_id, COUNT(u.id) AS num_consultants
FROM user u
WHERE u.is_active = 1 AND u.type = 0
GROUP BY u.country_id) y ON y.country_id = c.id