sql：
/* Navicat Premium Data Transfer Source Server : localhost Source Server Type : MySQL Source Server Version : 50724 Source Host : localhost:3306 Source Schema : local_test Target Server Type : MySQL Target Server Version : 50724 File Encoding : 65001 Date: 25/03/2020 17:23:37 */ SET NAMES utf8mb4; SET FOREIGN_KEY_CHECKS = 0; -- ---------------------------- -- Table structure for citys -- ---------------------------- DROP TABLE IF EXISTS `citys`; CREATE TABLE `citys` ( `id` int(5) NOT NULL AUTO_INCREMENT COMMENT 'id', `pid` int(5) NULL DEFAULT NULL COMMENT '父id', `city` varchar(100) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '城市', PRIMARY KEY (`id`) USING BTREE ) ENGINE = InnoDB AUTO_INCREMENT = 8 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic; -- ---------------------------- -- Records of citys -- ---------------------------- INSERT INTO `citys` VALUES (1, 0, '湖南'); INSERT INTO `citys` VALUES (2, 0, '江西'); INSERT INTO `citys` VALUES (3, 0, '广东'); INSERT INTO `citys` VALUES (4, 1, '长沙'); INSERT INTO `citys` VALUES (5, 1, '常德'); INSERT INTO `citys` VALUES (6, 1, '岳阳'); INSERT INTO `citys` VALUES (7, 2, '萍乡'); SET FOREIGN_KEY_CHECKS = 1;