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mysql 分組聯合查詢,按聯合mysql分組查詢

mysql 分組聯合查詢,按聯合mysql分組查詢

(SELECT COUNT(motorbike.`owner_id`) as count,owner.`name`,transport.`type` FROM transport,owner,motorbike WHERE transport.type='motobike'

AND owner.`owner_id`=motorbike.`owner_id`

AND transport.`type_id`=motorbike.`motorbike_id` GROUP BY motorbike.owner_id)

UNION ALL

(SELECT COUNT(car.`owner_id`) as count,owner.`name`,transport.`type` FROM transport,owner,car WHERE transport.type='car'

AND owner.`owner_id`=car.`owner_id`

AND transport.`type_id`=car.`car_id` GROUP BY car.`owner_id`)

The query above returns a result like this below,

count name

1 Linda

2 Mary

1 Steve

1 Linda

This query is to count how many transport that owned by an owner. Linda have one car and one motorcycle,so the result should:

count name

2 Linda

2 Mary

1 Steve

I have tried this query,but return error:

(SELECT COUNT(motorbike.`owner_id`),owner.`name`,transport.`type` FROM transport,owner,motorbike WHERE transport.type='motobike'

AND owner.`owner_id`=motorbike.`owner_id`

AND transport.`type_id`=motorbike.`motorbike_id`)

UNION ALL

(SELECT COUNT(car.`owner_id`),owner.`name`,transport.`type` FROM transport,owner,car WHERE transport.type='car'

AND owner.`owner_id`=car.`owner_id`

AND transport.`type_id`=car.`car_id`) GROUP BY motorbike.owner_id

Can anyone help me please?

解決方案select sum(qty), name

from (

select count(m.owner_id) as qty, o.name

from transport t,owner o,motorbike m

where t.type='motobike' and o.owner_id=m.owner_id

and t.type_id=m.motorbike_id

group by m.owner_id

union all

select count(c.owner_id) as qty, o.name,

from transport t,owner o,car c

where t.type='car' and o.owner_id=c.owner_id and t.type_id=c.car_id

group by c.owner_id

) t

group by name