http://sqlfiddle.com/#!9/5ad1fb/4
SELECT u.*, COUNT(ut.id) property_count
FROM users_table u
LEFT JOIN users_table ut
ON u.id = ut.property_id
WHERE u.admin = 1
GROUP BY u.id, u.name, u.admin
在mysql的同一张表中找到许多匹配到一行
http://sqlfiddle.com/#!9/5ad1fb/4
SELECT u.*, COUNT(ut.id) property_count
FROM users_table u
LEFT JOIN users_table ut
ON u.id = ut.property_id
WHERE u.admin = 1
GROUP BY u.id, u.name, u.admin