mysql使用变量存储.根据子ID找到父ID

 

根据子ID找到父ID

 

SELECT T2.id, T2.name

FROM (

    SELECT

        @r AS _id,

        (SELECT @r := parent_id FROM table1 WHERE id = _id) AS parent_id,

        @l := @l + 1 AS lvl

    FROM

        (SELECT @r := 5, @l := 0) vars,

        table1 h

    WHERE @r <> 0) T1

JOIN table1 T2

ON T1._id = T2.id

ORDER BY T1.lvl DESC

 

更改         (SELECT @r := 5, @l := 0) vars,   @r的数据

 

 

 

 转:https://www.cnblogs.com/interdrp/p/8018071.html