sql 连接查询获取一条null数据

将left join 查询换成对应的and 多条件联合查询

SELECT
        e.id AS id
    FROM
        s_roles r
    LEFT JOIN s_roleResource e ON r.id = e.roleId
    WHERE
        r.id = #{id}

=====》换成

SELECT
        e.id AS id
    FROM
        s_roles r ,  s_roleResource e  
    WHERE
        r.id = #{id} and r.id = e.roleId