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mysql set names.

SET NAMES utf8

相当于

SET character_set_client = utf8 --用来设置客户端送给MySQL服务器的数据的 字符集
SET character_set_results = utf8 --服务器返回查询结果时使用的字符集
SET character_set_connection = utf8

MySQL 服务器 把客户端传来的数据,从character_set_client字符集转换成character_set_connection字符集
比如我们可以设置

SET character_set_client = gbk
SET character_set_results = gbk
--
SET character_set_connection = utf8

这样数据在 MySQL内部的存储表示 为 utf8 字符集,而 与 客户端交互时,使用gbk字符集合

ref: 谈谈MySQL乱码和set names

我个人觉得,由于本地机为gbk编码,所以,即使创建数据库时的编码是utf8,当我们录入数据时,仍然需要告诉mysql,本地机器编码为gbk.

为了不至于每次录入数据库都输入命令 ‘set names gbk‘.我们可以再 mysql的安装目录中(我的安装目录为C盘),C:\Program Files (x86)\MySQL\MySQL Server 5.5下的 ‘my,ini‘文件下,[client]附近处的 ‘default-character-set=utf8‘ 改为 ‘default-character-set=gbk‘即可.如,我的原始 my.ini为:

  1 # MySQL Server Instance Configuration File
  2 # ----------------------------------------------------------------------
  3 # Generated by the MySQL Server Instance Configuration Wizard
  4 #
  5 #
  6 # Installation Instructions
  7 # ----------------------------------------------------------------------
  8 #
  9 # On Linux you can copy this file to /etc/my.cnf to set global options,
 10 # mysql-data-dir/my.cnf to set server-specific options
 11 # (@localstatedir@ for this installation) or to
 12 # ~/.my.cnf to set user-specific options.
 13 #
 14 # On Windows you should keep this file in the installation directory 
 15 # of your server (e.g. C:\Program Files\MySQL\MySQL Server X.Y). To
 16 # make sure the server reads the config file use the startup option 
 17 # "--defaults-file". 
 18 #
 19 # To run run the server from the command line, execute this in a 
 20 # command line shell, e.g.
 21 # mysqld --defaults-file="C:\Program Files\MySQL\MySQL Server X.Y\my.ini"
 22 #
 23 # To install the server as a Windows service manually, execute this in a 
 24 # command line shell, e.g.
 25 # mysqld --install MySQLXY --defaults-file="C:\Program Files\MySQL\MySQL Server X.Y\my.ini"
 26 #
 27 # And then execute this in a command line shell to start the server, e.g.
 28 # net start MySQLXY
 29 #
 30 #
 31 # Guildlines for editing this file
 32 # ----------------------------------------------------------------------
 33 #
 34 # In this file, you can use all long options that the program supports.
 35 # If you want to know the options a program supports, start the program
 36 # with the "--help" option.
 37 #
 38 # More detailed information about the individual options can also be
 39 # found in the manual.
 40 #
 41 #
 42 # CLIENT SECTION
 43 # ----------------------------------------------------------------------
 44 #
 45 # The following options will be read by MySQL client applications.
 46 # Note that only client applications shipped by MySQL are guaranteed
 47 # to read this section. If you want your own MySQL client program to
 48 # honor these values, you need to specify it as an option during the
 49 # MySQL client library initialization.
 50 #
 51 [client]
 52 
 53 port=3306
 54 
 55 [mysql]
 56 
 57 default-character-set=utf8
 58 
 59 
 60 # SERVER SECTION
 61 # ----------------------------------------------------------------------
 62 #
 63 # The following options will be read by the MySQL Server. Make sure that
 64 # you have installed the server correctly (see above) so it reads this 
 65 # file.
 66 #
 67 [mysqld]
 68 
 69 # The TCP/IP Port the MySQL Server will listen on
 70 port=3306
 71 
 72 
 73 #Path to installation directory. All paths are usually resolved relative to this.
 74 basedir="C:/Program Files (x86)/MySQL/MySQL Server 5.5/"
 75 
 76 #Path to the database root
 77 datadir="C:/ProgramData/MySQL/MySQL Server 5.5/Data/"
 78 
 79 # The default character set that will be used when a new schema or table is
 80 # created and no character set is defined
 81 character-set-server=utf8
 82 
 83 # The default storage engine that will be used when create new tables when
 84 default-storage-engine=INNODB
 85 
 86 # Set the SQL mode to strict
 87 sql-mode="STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"
 88 
 89 # The maximum amount of concurrent sessions the MySQL server will
 90 # allow. One of these connections will be reserved for a user with
 91 # SUPER privileges to allow the administrator to login even if the
 92 # connection limit has been reached.
 93 max_connections=100
 94 
 95 # Query cache is used to cache SELECT results and later return them
 96 # without actual executing the same query once again. Having the query
 97 # cache enabled may result in significant speed improvements, if your
 98 # have a lot of identical queries and rarely changing tables. See the
 99 # "Qcache_lowmem_prunes" status variable to check if the current value
100 # is high enough for your load.
101 # Note: In case your tables change very often or if your queries are
102 # textually different every time, the query cache may result in a
103 # slowdown instead of a performance improvement.
104 query_cache_size=0
105 
106 # The number of open tables for all threads. Increasing this value
107 # increases the number of file descriptors that mysqld requires.
108 # Therefore you have to make sure to set the amount of open files
109 # allowed to at least 4096 in the variable "open-files-limit" in
110 # section [mysqld_safe]
111 table_cache=256
112 
113 # Maximum size for internal (in-memory) temporary tables. If a table
114 # grows larger than this value, it is automatically converted to disk
115 # based table This limitation is for a single table. There can be many
116 # of them.
117 tmp_table_size=35M
118 
119 
120 # How many threads we should keep in a cache for reuse. When a client
121 # disconnects, the client‘s threads are put in the cache if there aren‘t
122 # more than thread_cache_size threads from before.  This greatly reduces
123 # the amount of thread creations needed if you have a lot of new
124 # connections. (Normally this doesn‘t give a notable performance
125 # improvement if you have a good thread implementation.)
126 thread_cache_size=8
127 
128 #*** MyISAM Specific options
129 
130 # The maximum size of the temporary file MySQL is allowed to use while
131 # recreating the index (during REPAIR, ALTER TABLE or LOAD DATA INFILE.
132 # If the file-size would be bigger than this, the index will be created
133 # through the key cache (which is slower).
134 myisam_max_sort_file_size=100G
135 
136 # If the temporary file used for fast index creation would be bigger
137 # than using the key cache by the amount specified here, then prefer the
138 # key cache method.  This is mainly used to force long character keys in
139 # large tables to use the slower key cache method to create the index.
140 myisam_sort_buffer_size=69M
141 
142 # Size of the Key Buffer, used to cache index blocks for MyISAM tables.
143 # Do not set it larger than 30% of your available memory, as some memory
144 # is also required by the OS to cache rows. Even if you‘re not using
145 # MyISAM tables, you should still set it to 8-64M as it will also be
146 # used for internal temporary disk tables.
147 key_buffer_size=55M
148 
149 # Size of the buffer used for doing full table scans of MyISAM tables.
150 # Allocated per thread, if a full scan is needed.
151 read_buffer_size=64K
152 read_rnd_buffer_size=256K
153 
154 # This buffer is allocated when MySQL needs to rebuild the index in
155 # REPAIR, OPTIMZE, ALTER table statements as well as in LOAD DATA INFILE
156 # into an empty table. It is allocated per thread so be careful with
157 # large settings.
158 sort_buffer_size=256K
159 
160 
161 #*** INNODB Specific options ***
162 innodb_data_home_dir="D:/MySQL Datafiles/"
163 
164 # Use this option if you have a MySQL server with InnoDB support enabled
165 # but you do not plan to use it. This will save memory and disk space
166 # and speed up some things.
167 #skip-innodb
168 
169 # Additional memory pool that is used by InnoDB to store metadata
170 # information.  If InnoDB requires more memory for this purpose it will
171 # start to allocate it from the OS.  As this is fast enough on most
172 # recent operating systems, you normally do not need to change this
173 # value. SHOW INNODB STATUS will display the current amount used.
174 innodb_additional_mem_pool_size=3M
175 
176 # If set to 1, InnoDB will flush (fsync) the transaction logs to the
177 # disk at each commit, which offers full ACID behavior. If you are
178 # willing to compromise this safety, and you are running small
179 # transactions, you may set this to 0 or 2 to reduce disk I/O to the
180 # logs. Value 0 means that the log is only written to the log file and
181 # the log file flushed to disk approximately once per second. Value 2
182 # means the log is written to the log file at each commit, but the log
183 # file is only flushed to disk approximately once per second.
184 innodb_flush_log_at_trx_commit=1
185 
186 # The size of the buffer InnoDB uses for buffering log data. As soon as
187 # it is full, InnoDB will have to flush it to disk. As it is flushed
188 # once per second anyway, it does not make sense to have it very large
189 # (even with long transactions).
190 innodb_log_buffer_size=2M
191 
192 # InnoDB, unlike MyISAM, uses a buffer pool to cache both indexes and
193 # row data. The bigger you set this the less disk I/O is needed to
194 # access data in tables. On a dedicated database server you may set this
195 # parameter up to 80% of the machine physical memory size. Do not set it
196 # too large, though, because competition of the physical memory may
197 # cause paging in the operating system.  Note that on 32bit systems you
198 # might be limited to 2-3.5G of user level memory per process, so do not
199 # set it too high.
200 innodb_buffer_pool_size=107M
201 
202 # Size of each log file in a log group. You should set the combined size
203 # of log files to about 25%-100% of your buffer pool size to avoid
204 # unneeded buffer pool flush activity on log file overwrite. However,
205 # note that a larger logfile size will increase the time needed for the
206 # recovery process.
207 innodb_log_file_size=54M
208 
209 # Number of threads allowed inside the InnoDB kernel. The optimal value
210 # depends highly on the application, hardware as well as the OS
211 # scheduler properties. A too high value may lead to thread thrashing.
212 innodb_thread_concurrency=8

修改第 57行的 ‘default-character-set=utf8‘为 ‘default-character-set=gbk‘即可.重启服务后,即可.