Modify MySQL character encoding
Environment: CentOS + MySQL5.5.25a
1. First, log onto MySQL to check the default encoding. Latin encoding should exist and Chinese characters are not supported.
mysql> show variables like '%character%';
2. Disable MySQL
# /etc/init.d/mysql stop
3. Create and modify the configuration file.
Copy/usr/share/doc/mysql-server-5.1.52/my-large.cnf to/etc/my. cnf
Command: cp/usr/share/doc/mysql-server-5.1.52/my-large.cnf/etc/my. cnf
Open my. cnf and add configuration information
Add default-character-set = utf8 under the [client] Node
Add character_set_server = utf8 init_connect = 'set NAMES utf8' under the [mysqld] Node'
Add default-character-set = utf8 under the [mysql] Node
The modified configuration file my. cnf is as follows:
# Example MySQL config file for large systems.## This is for a large system with memory = 512M where the system runs mainly# MySQL.## MySQL programs look for option files in a set of# locations which depend on the deployment platform.# You can copy this option file to one of those# locations. For information about these locations, see:# http://dev.mysql.com/doc/mysql/en/option-files.html## In this file, you can use all long options that a program supports.# If you want to know which options a program supports, run the program# with the "--help" option.# The following options will be passed to all MySQL clients[client]#password= your_passwordport= 3306socket= /var/lib/mysql/mysql.sockdefault-character-set=utf8# Here follows entries for some specific programs# The MySQL server[mysqld]port= 3306socket= /var/lib/mysql/mysql.sockskip-external-lockingkey_buffer_size = 256Mmax_allowed_packet = 1Mtable_open_cache = 256sort_buffer_size = 1Mread_buffer_size = 1Mread_rnd_buffer_size = 4Mmyisam_sort_buffer_size = 64Mthread_cache_size = 8query_cache_size= 16M# Try number of CPU's*2 for thread_concurrencythread_concurrency = 8character_set_server=utf8init_connect='SET NAMES utf8'# Don't listen on a TCP/IP port at all. This can be a security enhancement,# if all processes that need to connect to mysqld run on the same host.# All interaction with mysqld must be made via Unix sockets or named pipes.# Note that using this option without enabling named pipes on Windows# (via the "enable-named-pipe" option) will render mysqld useless!# #skip-networking# Replication Master Server (default)# binary logging is required for replicationlog-bin=mysql-bin# binary logging format - mixed recommendedbinlog_format=mixed# required unique id between 1 and 2^32 - 1# defaults to 1 if master-host is not set# but will not function as a master if omittedserver-id= 1# Replication Slave (comment out master section to use this)## To configure this host as a replication slave, you can choose between# two methods :## 1) Use the CHANGE MASTER TO command (fully described in our manual) -# the syntax is:## CHANGE MASTER TO MASTER_HOST=
, MASTER_PORT=
,# MASTER_USER=
, MASTER_PASSWORD=
;## where you replace
,
,
by quoted strings and#
by the master's port number (3306 by default).## Example:## CHANGE MASTER TO MASTER_HOST='125.564.12.1', MASTER_PORT=3306,# MASTER_USER='joe', MASTER_PASSWORD='secret';## OR## 2) Set the variables below. However, in case you choose this method, then# start replication for the first time (even unsuccessfully, for example# if you mistyped the password in master-password and the slave fails to# connect), the slave will create a master.info file, and any later# change in this file to the variables' values below will be ignored and# overridden by the content of the master.info file, unless you shutdown# the slave server, delete master.info and restart the slaver server.# For that reason, you may want to leave the lines below untouched# (commented) and instead use CHANGE MASTER TO (see above)## required unique id between 2 and 2^32 - 1# (and different from the master)# defaults to 2 if master-host is set# but will not function as a slave if omitted#server-id = 2## The replication master for this slave - required#master-host =
## The username the slave will use for authentication when connecting# to the master - required#master-user =
## The password the slave will authenticate with when connecting to# the master - required#master-password =
## The port the master is listening on.# optional - defaults to 3306#master-port =
## binary logging - not required for slaves, but recommended#log-bin=mysql-bin# Uncomment the following if you are using InnoDB tables#innodb_data_home_dir = /var/lib/mysql#innodb_data_file_path = ibdata1:10M:autoextend#innodb_log_group_home_dir = /var/lib/mysql# You can set .._buffer_pool_size up to 50 - 80 %# of RAM but beware of setting memory usage too high#innodb_buffer_pool_size = 256M#innodb_additional_mem_pool_size = 20M# Set .._log_file_size to 25 % of buffer pool size#innodb_log_file_size = 64M#innodb_log_buffer_size = 8M#innodb_flush_log_at_trx_commit = 1#innodb_lock_wait_timeout = 50[mysqldump]quickmax_allowed_packet = 16M[mysql]no-auto-rehash# Remove the next comment character if you are not familiar with SQL#safe-updatesdefault-character-set=utf8[myisamchk]key_buffer_size = 128Msort_buffer_size = 128Mread_buffer = 2Mwrite_buffer = 2M[mysqlhotcopy]interactive-timeout
4. Start MySQL
# /etc/init.d/mysql start
5. Check the encoding again.
mysql> show variables like '%character%';
Note: even if the above changes are made, if the database directly creates a table and then stores the table in Chinese, the question mark is returned.
The solution is to specify the default Character Set utf8 when creating a database, for example:
Create database test default character set utf8;