一、系统表空间扩容方法
方法1：在innodb_data_file_path参数后面加上autoextend参数
innodb_data_file_path=ibdata1:12M:autoextend

方法2：在innodb_data_file_path参数后面加上一个新的数据文件
innodb_data_file_path = /ibdata/ibdata1:988M;/disk2/ibdata2:50M:autoextend

二、操作步骤
1. 修改参数innodb_data_file_path
2. 关闭数据库，shutdown
3. 启动数据库，mysqld_safe &
4. 验证参数是否生效show variables like 'innodb_data_file_path';


三、案例
1. 查看默认参数
mysql> show variables like 'innodb_data%';
+-----------------------+------------------------+
| Variable_name         | Value                  |
+-----------------------+------------------------+
| innodb_data_file_path | ibdata1:12M:autoextend |
| innodb_data_home_dir  | /zxdata/my3311/data    |
+-----------------------+------------------------+
2 rows in set (0.00 sec)

2.关闭数据库
mysql>shutdown;

3.修改my.cnf参数文件
[root@roidb1 ~]# grep "path" /zxdata/my3311/etc/my.cnf
innodb_data_file_path              = ibdata1:12M;ibdata2:50M:autoextend

4.启动数据库
#/usr/local/mysql/bin/mysqld_safe --defaults-file=/zxdata/my3311/etc/my.cnf &

5.验证是否生效
mysql> show variables like 'innodb_data%';
+-----------------------+------------------------------------+
| Variable_name         | Value                              |
+-----------------------+------------------------------------+
| innodb_data_file_path | ibdata1:12M;ibdata2:50M:autoextend |
| innodb_data_home_dir  | /zxdata/my3311/data                |
+-----------------------+------------------------------------+
2 rows in set (0.01 sec)