来自一个查询中的一个表的SQL子组

Question

我有一个分类表，其中包含具有相应类型的国家，州，地区和城镇。项目的父项是它所在的区域，州或国家。然后是一个包含这些ID的对象的表格。特定的类别和对象可能会被发布与否。

table: category 
id title  parent type published 
75 Spain  0  1  1 
76 Mallorca 75  2  1 
144 North  76  3  1 
149 South  76  3  1 
148 East  76  3  1 
147 West  76  3  1 
170 Cala  144  4  1 
195 Puebla  144  4  0 
166 Pica  149  4  1 
189 Playa  148  4  0 
199 Santa Ana 148  4  1 
247 Puerto  147  4  1 
... 

table: objects 
id title  country_id  state_id region_id town_id  published 
4 Alba  75    76   149   195   1 
5 Gris  75    76   144   170   1 
8 Casa  75    76   148   199   1 
8 Pueblo  75    76   147   247   1 
8 Don Carlo 75    76   148   199   1 
... 

结果应该是按类别类型是正确数量在每一个国家，州，区，镇对象的组合名称的列表。

id  title  parent  type   obj_count 
75  Spain  0   1   12 
76  Mallorca 75   2   4 
144  North  76   3   2 
149  South  76   3   3 
148  East  76   3   0 
147  West  76   3   1 
170  Cala  144   4   0 
166  Pica  149   4   1 
189  Playa  148   4   0 
195  Puebla  144   4   1 
247  Puerto  147   4   1 
199  Santa Ana 148   4   2 
and so on... 

查询我到目前为止返回名称的完整列表，以正确的顺序，但只有一个完整的计数（包括未公布）的城镇，但一旦我尝试检查“WHERE ob.published = 1 AND c.published = 1'它只返回城镇，而不是国家，州或地区。

SELECT 
c.id as id, c.title as title, c.type as type, c.parent as parent, 
count(ob.town_id) as obj_count 

FROM category AS c 
LEFT JOIN category AS r  ON c.id = r.parent 
LEFT JOIN category AS u  ON r.id = u.parent 
LEFT JOIN category AS o  ON u.id = o.parent 

LEFT JOIN objects AS ob  ON ob.town_id = c.id 

WHERE 1 
GROUP BY type, id, parent 
ORDER BY parent, title 

任何人都可以帮助我在一个查询中做到这一点？谢谢。

Answer 1

SELECT c.id, c.title, c.type, count(c.id) as cnt 
FROM category c 
LEFT JOIN objects o ON (o.country_id = c.id OR o.state_id = c.id OR o.region_id = c.id OR o.town_id = c.id) 
GROUP BY c.id 
ORDER by type