from : http://www.cnblogs.com/edrh/archive/2007/09/04/881054.html

1.首先确认你日志是否启用了
mysql>show variables like 'log_bin';
2.如果启用了，即ON
那日志文件就在mysql的安装目录的data目录下
3.怎样知道当前的日志
mysql> show master status;                                                                                                                                               
4.看二进制日志文件用mysqlbinlog
shell>mysqlbinlog mail-bin.000001
或者shell>mysqlbinlog mail-bin.000001 | tail

Windows 下用类似的命令。