关于java连接MYSQL中文乱码处理

java连接mysql中参数的中文乱码问题

1，在创建mysql数据库时，需要在mysql目录下添加my.ini文件

[mysqld]
character-set-server=utf8
#绑定IPv4和3306端口
bind-address = 0.0.0.0
port = 3306
# 设置mysql的安装目录
basedir=C:\Program Files\MySQL\MySQL Server 5.5
# 设置mysql数据库的数据的存放目录
datadir=C:\Program Files\MySQL\MySQL Server 5.5\data
# 允许最大连接数
max_connections=200
# skip_grant_tables
[mysql]
default-character-set=utf8
[mysql.server]
default-character-set=utf8
[mysql_safe]
default-character-set=utf8
[client]

default-character-set=utf8

修改完成后打开cmd  启动mysql

启动mysql

net start mysql 

停止mysql

net stop mysql 

启动完成后进入mysql

查看

show variables like 'character%';

2，数据库字段编码格式查看

3、查看 MySQL 数据表（table） 的字符集。

mysql> show table status from sqlstudy_db like '%countries%';
+-----------+--------+---------+------------+------+-----------------+------
| Name | Engine | Version | Row_format | Rows | Collation |......
+-----------+--------+---------+------------+------+-----------------+------
| countries | InnoDB | 10 | Compact | 11 | utf8_general_ci |......
+-----------+--------+---------+------------+------+-----------------+------

4、查看 MySQL 数据列（column）的字符集。


mysql> show full columns from countries;
+----------------------+-------------+-----------------+--------
| Field | Type | Collation | .......
+----------------------+-------------+-----------------+--------
| countries_id | int(11) | NULL | .......
| countries_name | varchar(64) | utf8_general_ci | .......
| countries_iso_code_2 | char(2) | utf8_general_ci | .......
| countries_iso_code_3 | char(3) | utf8_general_ci | .......
| address_format_id | int(11) | NULL | .......

+----------------------+-------------+-----------------+--------

5、查看当前安装的 MySQL 所支持的字符集。


mysql> show charset;
mysql> show char set;
+----------+-----------------------------+---------------------+--------+
| Charset | Description | Default collation | Maxlen |
+----------+-----------------------------+---------------------+--------+
| big5 | Big5 Traditional Chinese | big5_chinese_ci | 2 |
| dec8 | DEC West European | dec8_swedish_ci | 1 |
| cp850 | DOS West European | cp850_general_ci | 1 |
| hp8 | HP West European | hp8_english_ci | 1 |
| koi8r | KOI8-R Relcom Russian | koi8r_general_ci | 1 |
| latin1 | cp1252 West European | latin1_swedish_ci | 1 |
| latin2 | ISO 8859-2 Central European | latin2_general_ci | 1 |
| swe7 | 7bit Swedish | swe7_swedish_ci | 1 |
| ascii | US ASCII | ascii_general_ci | 1 |
| ujis | EUC-JP Japanese | ujis_japanese_ci | 3 |
| sjis | Shift-JIS Japanese | sjis_japanese_ci | 2 |
| hebrew | ISO 8859-8 Hebrew | hebrew_general_ci | 1 |
| tis620 | TIS620 Thai | tis620_thai_ci | 1 |
| euckr | EUC-KR Korean | euckr_korean_ci | 2 |

| koi8u | KOI8-U 

6、修改表和字段的字符集
//修改数据库
mysql> alter database name character set utf8;
//修改表
alter table 表名 convert to character set gbk;
//修改字段
alter table 表名 modify column '字段名' varchar(30) character set gbk not null;
//添加表字段
alter table 表名 add column '字段名' varchar (20) character set gbk;
注:执行命令过程中字段名不加引号