# MYSQL根据id递归向下查询所有子级
# 1 递归查询sql
SELECT
ID.LEVEL,
DATA.*
FROM
(
SELECT
@ids AS _ids,
( SELECT @ids := GROUP_CONCAT( id ) FROM 表名 WHERE FIND_IN_SET( 父级 id字段, @ids ) ) AS cids,
@l := @l + 1 AS LEVEL
FROM
表名,
( SELECT @ids := '条件id', @l := 0 ) b
WHERE
@ids IS NOT NULL
) ID,
表名 DATA
WHERE
FIND_IN_SET( DATA.id, ID._ids )
ORDER BY
LEVEL,
id
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