MySQL去重保留最大的那条记录（取最新的记录）以用户登录日志表为例，取用户最近登录的设备1 SET NAMES utf8mb4;2 SET FOREIGN_KEY_CHECKS = 0;34 -- ----------------------------5 -- Table structure for t_login_log6 -- ----------------------------7 DROP TABLE IF EXISTS `t_login_log`;8 CREATE TABLE `t_login_log` (9 `id` int(11) NOT NULL AUTO_INCREMENT,10 `user_id` int(11) NOT NULL COMMENT '用户ID',11 `device_name` varchar(32) COLLATE utf8mb4_bin NOT NULL COMMENT '登录设备',12 `login_time` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT '登录时间',13 PRIMARY KEY (`id`)14 ) ENGINE=InnoDB AUTO_INCREMENT=9 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin;1516 -- ----------------------------17 -- Records of t_login_log18 -- ----------------------------19 BEGIN;20 INSERT INTO `t_login_log` VALUES (1, 1121, 'iPhone 6s', '-07-01 19:20:25');21 INSERT INTO `t_login_log` VALUES (2, 2120, 'vivo x20', '-06-28 16:21:11');22 INSERT INTO `t_login_log` VALUES (3, 1607, 'huawei P30', '-07-04 19:21:59');23 INSERT INTO `t_login_log` VALUES (4, 2120, 'vivo x20', '-06-30 19:22:34');24 INSERT INTO `t_login_log` VALUES (5, 2120, 'vivo x20', '-07-04 19:23:07');25 INSERT INTO `t_login_log` VALUES (6, 1121, 'iPad mini', '-07-03 19:23:25');26 INSERT INTO `t_login_log` VALUES (7, 1607, 'iPhone 8 Plus', '-06-30 19:24:06');27 INSERT INTO `t_login_log` VALUES (8, 1970, 'MI8', '-07-03 19:25:00');28 COMMIT;2930 SET FOREIGN_KEY_CHECKS = 1;。