select * from system_skin where ss_id=#{systemSkinId} select * from system_skin; select * from system_skin left join system_skin_manager on ss_id=ssm_system_skin_ID where ssm_managerID=#{managerId} update system_skin_manager set ssm_system_skin_ID=#{systemSkinId} where ssm_managerID=#{managerId} insert into system_skin_manager values(#{managerId},#{systemSkinId});