mysql 根据父类id，查所有的子类树

数据库表记录示例如下：

 

mysql：

SELECT
	ID.LEVEL,
	DATA.* 
FROM
	(
	SELECT
		@ids AS _ids,
		( SELECT @ids := GROUP_CONCAT( id ) FROM sys_depart WHERE FIND_IN_SET( parent_id, @ids ) ) AS cids,
		@l := @l + 1 AS LEVEL 
	FROM
		sys_depart,
		( SELECT @ids := 'aadc6219f0dc4db683002f0172175033', @l := 0 ) b 
	WHERE
		@ids IS NOT NULL 
	) id,
	sys_depart DATA 
WHERE
	FIND_IN_SET( DATA.id, ID._ids ) 
ORDER BY
	LEVEL,
	id;