MySQL 导入问题

Question

我正在尝试将数据库从一个数据库导出到另一个数据库。我正在使用以下命令来导出和导入：

export: mysqldump -u root -p dwad dwadallauth.sql
import: $ mysql -u root -p dwad < dwadallauth.sql

然后我检查了一下，很明显原始数据库是使用以下方法创建的：

CREATE DATABASE dwad CHARACTER SET utf8 COLLATE utf8_general_ci;

然后授予权限如下：

GRANT ALL PRIVILEGES ON dwad.* TO 'dwad'@'localhost' IDENTIFIED BY '9LSo1SxqdJF45PL';

所以我尝试了以下导入：

import: $ mysql -u root -p --default-character-set=utf8 dwad < dwadallauth.sql

但是，每当我尝试导入时，我都会收到以下错误：

ERROR 1064 (42000) at line 54: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '(6) NOT NULL,
  `sent` datetime(6) DEFAULT NULL,
  `key` varchar(64) NOT NULL,
 ' at line 3

我查了一下，MySQL的版本如下：

Export: mysql  Ver 14.14 Distrib 5.7.13, for Linux (armv7l) using  EditLine wrapper

Import: mysql  Ver 14.14 Distrib 5.5.50, for debian-linux-gnu (x86_64) using readline 6.3

我希望有人能指出我正确的方向，在此先感谢。

PS

以下是导出创建的 SQL 文件的副本：

-- MySQL dump 10.13  Distrib 5.7.13, for Linux (armv7l)
--
-- Host: localhost    Database: dwad
-- ------------------------------------------------------
-- Server version       5.7.13-0ubuntu0.16.04.2

/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;

/*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */;

/*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */;
/*!40101 SET NAMES utf8 */;

/*!40103 SET @OLD_TIME_ZONE=@@TIME_ZONE */;

/*!40103 SET TIME_ZONE='+00:00' */;

/*!40014 SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0 */;

/*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */;

/*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */;

/*!40111 SET @OLD_SQL_NOTES=@@SQL_NOTES, SQL_NOTES=0 */;

--
-- Table structure for table `account_emailaddress`
--

DROP TABLE IF EXISTS `account_emailaddress`;
/*!40101 SET @saved_cs_client     = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `account_emailaddress` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `email` varchar(254) NOT NULL,
  `verified` tinyint(1) NOT NULL,
  `primary` tinyint(1) NOT NULL,
  `user_id` int(11) NOT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `email` (`email`),
  KEY `account_emailaddress_user_id_2c513194_fk_auth_user_id` (`user_id`),
  CONSTRAINT `account_emailaddress_user_id_2c513194_fk_auth_user_id` FOREIGN KEY (`user_id`) REFERENCES `auth_user` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
/*!40101 SET character_set_client = @saved_cs_client */;

--
-- Dumping data for table `account_emailaddress`
--

LOCK TABLES `account_emailaddress` WRITE;
/*!40000 ALTER TABLE `account_emailaddress` DISABLE KEYS */;
/*!40000 ALTER TABLE `account_emailaddress` ENABLE KEYS */;
UNLOCK TABLES;

--
-- Table structure for table `account_emailconfirmation`
--

DROP TABLE IF EXISTS `account_emailconfirmation`;
/*!40101 SET @saved_cs_client     = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `account_emailconfirmation` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `created` datetime(6) NOT NULL,
  `sent` datetime(6) DEFAULT NULL,
  `key` varchar(64) NOT NULL,
  `email_address_id` int(11) NOT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `key` (`key`),
  KEY `account_ema_email_address_id_5b7f8c58_fk_account_emailaddress_id` (`email_address_id`),
  CONSTRAINT `account_ema_email_address_id_5b7f8c58_fk_account_emailaddress_id` FOREIGN KEY (`email_address_id`) REFERENCES `account_emailaddress` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
/*!40101 SET character_set_client = @saved_cs_client */;

Answer 1

根据mysql 5.7的手册：

支持使用逻辑降级方法降级多个版本级别，但前提是您一次降级一个版本级别。例如，您可以从 5.7 降级到 5.6，然后再降到 5.5。

您正在尝试一步从 5.7 升级到 5.5。这可能会导致您的问题。

见https://dev.mysql.com/doc/refman/5.7/en/downgrading.html

Answer 2

datetime(6) 在旧版本中不受支持。在降级期间，您将不得不损失微秒。