my.ini文件内容：
[mysqld]
port  = 3307
basedir=D:/wamp2/mysql
tmpdir=D:/wamp2/tmp/

sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES
变量的默认值：
init_file                      
old_passwords                   OFF
port                            3307
protocol_version                10
server_id                       0
version                         5.5.34
version_comment                 MySQL Community Server (GPL)
version_compile_machine         x86
version_compile_os              Win64
concurrent_insert               AUTO
have_compress                   YES
have_crypt                      NO
have_innodb                     YES
have_openssl                    DISABLED
have_query_cache                YES
have_symlink                    YES
large_files_support             ON
local_infile                    ON
low_priority_updates            OFF
lower_case_table_names          1
named_pipe                      OFF
new                             OFF
read_only                       OFF
skip_networking                 OFF
basedir                         D:/wamp2/mysql
datadir                         D:\wamp2\mysql\data\
innodb_data_file_path           ibdata1:10M:autoextend
innodb_log_group_home_dir       .\
log_error