请教查询用户的客户数量的 SQL 写法 [ 2.0 版本 ]

SELECT
	`customer`.`user_id`,
	`user`.`username`,
	`user`.`real_name`,
	sum(real_paid) AS sales,
	count(*) AS count
FROM `customer`	
LEFT JOIN `invoice` ON `invoice`.customer_id = `customer`.id
LEFT JOIN `user` ON `customer`.user_id = `user` .id
WHERE
	`customer`.`company_id` = 116
GROUP BY
	`customer`.`user_id`

查出来的 count 都是错来的,比实际多了很多,拜托各位大神帮忙看看,感谢