这是我的sql
<select id="selectTreeByParent_id" parameterType="java.util.HashMap" resultMap="BaseResultMap">
SELECT
ID.LEVEL1,
DATA1.*
FROM
(
SELECT
@ids AS _ids,
( SELECT @ids := GROUP_CONCAT( gid ) FROM project_grouping WHERE FIND_IN_SET( parent_id, @ids ) ) AS cids,
@l := @l + 1 AS LEVEL1
FROM
project_grouping,
( SELECT @ids := #{parent_id}, @l := -1 ) b
WHERE
@ids IS NOT NULL
) ID,
project_grouping DATA1
WHERE
FIND_IN_SET( DATA1.gid, ID._ids )
<if test="gid!=null">
AND gid = #{gid}
</if>
ORDER BY
LEVEL1,
gid
</select>
查询结构这问题太困扰我了,鼓捣两天了,可以再加分,求大佬救我
<select id="selectTreeByParent_id" parameterType="java.util.HashMap" resultMap="BaseResultMap">
SELECT
ID.LEVEL1,
DATA1.*
FROM
(
SELECT
@ids AS _ids,
( SELECT @ids := GROUP_CONCAT( gid ) FROM project_grouping WHERE FIND_IN_SET( parent_id, @ids ) ) AS cids,
@l := @l + 1 AS LEVEL1
FROM
project_grouping,
( SELECT @ids := #{parent_id}, @l := -1 ) b
WHERE
@ids IS NOT NULL
) ID,
project_grouping DATA1
WHERE
FIND_IN_SET( DATA1.gid, ID._ids )
<if test="gid!=null">
AND gid = #{gid}
</if>
ORDER BY
LEVEL1,
gid
</select>
查询结构这问题太困扰我了,鼓捣两天了,可以再加分,求大佬救我
第一次15 第二次5