SELECT v.name
,COUNT(DISTINCT f.ID
)AS family,COUNT(DISTINCT p.ID
)AS person ,COUNT(DISTINCT pa.ID
) AS man,COUNT(DISTINCT ps.ID
)AS woman ,COUNT(DISTINCT c.id
)AS car
FROM village AS v
LEFT JOIN family AS f ON f.villageID
=v.ID
AND f.building
='3'
LEFT JOIN personnel AS p ON p.familyid
=f.ID
AND f.building
='3'
LEFT JOIN personnel AS pa ON pa.familyid
=f.ID
AND pa.sex
='男' AND f.building
='3'
LEFT JOIN personnel AS ps ON ps.familyid
=f.ID
AND ps.sex
='女' AND f.building
='3'
LEFT JOIN car AS c ON c.familyid
=f.ID
AND f.building
='3'
where v.ID
='d66cf963-2354-11e8-b8a0-f48e38f841f1'
GROUP BY f.building
已解决
https://www.cnblogs.com/kerrycode/p/5935704.html
这篇帖子对join的各种用法讲解比较清晰,可以参考一下