如何将笑脸插入MySQL（😊）

我在MySQL 5.5.21上，尝试插入'\ xF0 \ x9F \ x98 \ x8A'笑脸字符。但是对于我的一生，我不知道该怎么做。

根据我一直在阅读的各种论坛，这是可能的。但是只要我尝试一下，数据就会被截断。

mysql> INSERT INTO hour  (  `title`,   `content`,   `guid` ,  `published` , `lang` ,  `type` ,  
       `indegree` ,  `lon` ,  `lat` ,  `state` ,  `country` , `hour`  )   
       VALUES ( "title" ,  "content 😊  content" ,  "guid" ,  1,  1,   
                     "WEBLOG",  1,  1,  1,  "state" ,  "country" ,  1 );
Query OK, 1 row affected, 2 warnings (0.00 sec)

mysql> show warnings;
+---------+------+-------------------------------------------------------------------------------+
| Level   | Code | Message                                                                       |
+---------+------+-------------------------------------------------------------------------------+
| Warning | 1366 | Incorrect string value: '\xF0\x9F\x98\x8A  ...' for column 'content' at row 1 |
| Warning | 1265 | Data truncated for column 'published' at row 1                                |
+---------+------+-------------------------------------------------------------------------------+
2 rows in set (0.00 sec)

mysql> select LAST_INSERT_ID();
+------------------+
| LAST_INSERT_ID() |
+------------------+
|           687302 |
+------------------+
1 row in set (0.00 sec)

mysql> select * from hour where id = 687302;
+--------+-------+----------+------+---------------------+
| id     | title | content  | guid | published           |
+--------+-------+----------+------+---------------------+
| 687302 | title | content  | guid | 0000-00-00 00:00:00 |
+--------+-------+----------+------+---------------------+
1 row in set (0.00 sec)

但是我的表定义如下。

CREATE TABLE `hour` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `title` varchar(255) CHARACTER SET utf8 NOT NULL,
  `content` text CHARACTER SET utf8 NOT NULL,
  `guid` varchar(255) CHARACTER SET utf8 NOT NULL,
  `published` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  `lang` tinyint(3) unsigned NOT NULL,
  `type` enum('WEBLOG','MICROBLOG') CHARACTER SET utf8 DEFAULT NULL,
  `indegree` int(4) unsigned NOT NULL,
  `lon` float DEFAULT NULL,
  `lat` float DEFAULT NULL,
  `state` varchar(50) CHARACTER SET utf8 DEFAULT '',
  `country` varchar(50) CHARACTER SET utf8 DEFAULT '',
  `hour` int(2) DEFAULT NULL,
  `gender` enum('MALE','FEMALE') CHARACTER SET utf8 DEFAULT NULL,
  `time_zone` varchar(45) CHARACTER SET utf8 DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=MEMORY AUTO_INCREMENT=687560 DEFAULT CHARSET=utf8mb4 KEY_BLOCK_SIZE=288 

可以看到我正在使用CHARSET = utf8mb4。这样肯定可以解决多字节字符使用方面的问题吗？

好的，所以我没有注意到：

  `content` text CHARACTER SET utf8 NOT NULL,

我已经纠正了这个问题，但仍然得到了一些时髦的结果。

CREATE TABLE `hourtmp` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `title` varchar(255) CHARACTER SET utf8 NOT NULL,
  `content` text NOT NULL,
  `guid` varchar(255) CHARACTER SET utf8 NOT NULL,
  `published` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  `lang` tinyint(3) unsigned NOT NULL,
  `type` enum('WEBLOG','MICROBLOG') CHARACTER SET utf8 DEFAULT NULL,
  `indegree` int(4) unsigned NOT NULL,
  `lon` float DEFAULT NULL,
  `lat` float DEFAULT NULL,
  `state` varchar(50) CHARACTER SET utf8 DEFAULT '',
  `country` varchar(50) CHARACTER SET utf8 DEFAULT '',
  `hour` int(2) DEFAULT NULL,
  `gender` enum('MALE','FEMALE') CHARACTER SET utf8 DEFAULT NULL,
  `time_zone` varchar(45) CHARACTER SET utf8 DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=MEMORY AUTO_INCREMENT=687563 DEFAULT CHARSET=utf8mb4 KEY_BLOCK_SIZE=288 |

 mysql> INSERT INTO hourtmp  (  `title`,   `content`,   `guid` ,  `published` , `lang` ,  `type` ,  `indegree` ,  
 `lon` ,  `lat` ,  `state` ,  `country` , `hour`  )   VALUES ( "title" ,  "content 😊  content" ,  
 "guid" ,  1,  1,   "WEBLOG",  1,  1,  1,  "state" ,  "country" ,  1 );
 Query OK, 1 row affected, 2 warnings (0.00 sec)

 mysql> show warnings;

 | Level   | Code | Message                                                                       |

 | Warning | 1366 | Incorrect string value: '\xF0\x9F\x98\x8A  ...' for column 'content' at row 1 |
 | Warning | 1265 | Data truncated for column 'published' at row 1                                |

 2 rows in set (0.00 sec)

 mysql> select * from hourtmp;
 +--------+-------+-----------------------+
 | id     | title | content               |
 +--------+-------+-----------------------+
 | 687560 | title | content ????  content |
 | 687561 | title | content ????  content |
 +--------+-------+-----------------------+

我最近写了一份详细的指南，介绍如何从MySQL切换utf8到utf8mb4。如果您按照此处的步骤操作，则所有内容均应正常运行。这是过程中每个步骤的直接链接：

• 步骤1：建立备份
• 步骤2：升级MySQL服务器
• 步骤3：修改数据库，表和列
• 步骤4：检查列和索引键的最大长度
• 步骤5：修改连接，客户端和服务器字符集
• 步骤6：修复和优化所有表

我怀疑通过执行步骤5可以解决您的问题。希望这对您有所帮助！

请执行以下操作：

1. 将数据库字符集设置为utf8mb4

2. 将列的字符集设置为utf8mb4

像下面的查询：

ALTER TABLE `comments` CHANGE `text` `text` VARCHAR(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL;