mysql横向转纵向、纵向转横向排列的方法

初始化数据 DROP TABLE IF EXISTS `test_01`; CREATE TABLE `test_01` ( `id` int(0) NOT NULL, `user` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '用户', `km` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '科目', `fs` varch