mysql为啥不能插入数据
mysql为何不能插入数据?
安装AppServ后首次使用mysql,没有图形界面,在“MySql Command Line Client”的操作如下:
======================================================================================
mysql> create database cars;
Query OK, 1 row affected (0.00 sec)
mysql> use cars;
Database changed
mysql> create table cars(id int,xm char(8),h char(8),vin char(20));
Query OK, 0 rows affected (0.06 sec)
mysql> insert into cars(id,xm,h,vin) values(1,'廉东方','豫A5F568','LDC666L2980790000');
Query OK, 1 row affected, 1 warning (0.02 sec)
mysql> select * from cars;
+------+------+----------+-------------------+
| id | xm | h | vin |
+------+------+----------+-------------------+
| 1 | | 豫A5F568 | LDC666L2980790000 |
+------+------+----------+-------------------+
1 rows in set (0.02 sec)
mysql> select xm from cars;
+------+
| xm |
+------+
| |
+------+
1 rows in set (0.00 sec)
mysql> update cars set xm='廉' where id=1;
Query OK, 0 rows affected, 1 warning (0.01 sec)
Rows matched: 1 Changed: 0 Warnings: 0
为何不能设置xm字段的值?为何无法更新?谢谢啦~~~
------解决方案--------------------
你 #1 的内容是我在#3回复后才看到的,不然一开始就解释了
\xC1\xAE\xB6\xAB\xB7\xBD 是 廉东方 的gbk 内码
而他却报错了,这说明你的数据库的默认字符集不是 latin1 的,也不是 gbk 的
那么对中文报错就只能是 utf8 的了(极少有人用 ucs-2 的,就算是也没关系)
对 utf8 字段插入 gbk 字符当然就要报错了
所以要 set names gbk 通知 mysql 现在用的是 gbk 字符
那么“豫”为什么没有报错呢?
这就要看 utf-8 是如何编码的了:
U+007F 0xxxxxxx
U+07FF 110xxxxx 10xxxxxx
U+FFFF 1110xxxx 10xxxxxx 10xxxxxx
U+1FFFFF 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
U+3FFFFFF 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
U+7FFFFFFF 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
豫 的gbk二进制内码为 11010100 10100101
正好符合 U+07FF 编码规则,所以他就不会报错

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