MySQL配置文件my.ini的使用解读_Mysql

my.ini 是啥玩意？

my.ini是MySQL数据库中使用的配置文件，修改这个文件可以达到更新配置的目的。

my.ini 在哪放着呢？

my.ini存放在MySql安装的根目录，如图所示：（我比较懒，用的WAMP，大家找自己的安装目录即可）

MySQL配置文件my.ini的使用解读

my.ini的配置内容介绍

其实大体可以分为两部分：客户端的参数、服务器参数。

其中服务器参数里还包括 InnoDB存储引擎参数。

客户端的参数

下面显示的是客户端的参数，[client]和[mysql]都是客户端，下面是参数简介：

port参数表示的是MySQL数据库的端口，默认的端口是3306，如果你需要更改端口号的话，就可以通过在这里修改。
default-character-set参数是客户端默认的字符集，如果你希望它支持中文，可以设置成gbk或者utf8。
这里还有一个password参数，在这里设置了password参数的值就可以在登陆时不用输入密码直接进入

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									# CLIENT SECTION

									# ----------------------------------------------------------------------

									#

									# The following options will be read by MySQL client applications.

									# Note that only client applications shipped by MySQL are guaranteed

									# to read this section. If you want your own MySQL client program to

									# honor these values, you need to specify it as an option during the

									# MySQL client library initialization.

									#

									[client]

									port=3306

									[mysql]

									default-character-set=gb2312

服务器断参数

以下是参数的介绍：

port参数也是表示数据库的端口。
basedir参数表示MySQL的安装路径。
datadir参数表示MySQL数据文件的存储位置，也是数据库表的存放位置。
default-character-set参数表示默认的字符集，这个字符集是服务器端的。
default-storage-engine参数默认的存储引擎。
这里有两个引擎 MyISAM 和 InnoDB ，用什么看你需求，详细介绍可以参考下面这篇文章：http://www.tuohang.net/article/270995.htm
sql-mode参数表示SQL模式的参数，通过这个参数可以设置检验SQL语句的严格程度。
max_connections参数表示允许同时访问MySQL服务器的最大连接数，其中一个连接是保留的，留给管理员专用的。
query_cache_size参数表示查询时的缓存大小，缓存中可以存储以前通过select语句查询过的信息，再次查询时就可以直接从缓存中拿出信息。
table_cache参数表示所有进程打开表的总数。
tmp_table_size参数表示内存中临时表的总数。
thread_cache_size参数表示保留客户端线程的缓存。
myisam_max_sort_file_size参数表示MySQL重建索引时所允许的最大临时文件的大小。
myisam_sort_buffer_size参数表示重建索引时的缓存大小。
key_buffer_size参数表示关键词的缓存大小。
read_buffer_size参数表示MyISAM表全表扫描的缓存大小。
read_rnd_buffer_size参数表示将排序好的数据存入该缓存中。
sort_buffer_size参数表示用于排序的缓存大小

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									# SERVER SECTION

									# ----------------------------------------------------------------------

									#

									# The following options will be read by the MySQL Server. Make sure that

									# you have installed the server correctly (see above) so it reads this

									# file.

									#

									[mysqld]

									# The TCP/IP Port the MySQL Server will listen on

									port=3306

									#Path to installation directory. All paths are usually resolved relative to this.

									basedir="E:/Java/Mysql/"

									#Path to the database root

									datadir="C:/ProgramData/MySQL/MySQL Server 5.5/Data/"

									# The default character set that will be used when a new schema or table is

									# created and no character set is defined

									character-set-server=gb2312

									# The default storage engine that will be used when create new tables when

									default-storage-engine=INNODB

									# Set the SQL mode to strict

									sql-mode="STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"

									# The maximum amount of concurrent sessions the MySQL server will

									# allow. One of these connections will be reserved for a user with

									# SUPER privileges to allow the administrator to login even if the

									# connection limit has been reached.

									max_connections=100

									# Query cache is used to cache SELECT results and later return them

									# without actual executing the same query once again. Having the query

									# cache enabled may result in significant speed improvements, if your

									# have a lot of identical queries and rarely changing tables. See the

									# "Qcache_lowmem_prunes" status variable to check if the current value

									# is high enough for your load.

									# Note: In case your tables change very often or if your queries are

									# textually different every time, the query cache may result in a

									# slowdown instead of a performance improvement.

									query_cache_size=0

									# The number of open tables for all threads. Increasing this value

									# increases the number of file descriptors that mysqld requires.

									# Therefore you have to make sure to set the amount of open files

									# allowed to at least 4096 in the variable "open-files-limit" in

									# section [mysqld_safe]

									table_cache=256

									# Maximum size for internal (in-memory) temporary tables. If a table

									# grows larger than this value, it is automatically converted to disk

									# based table This limitation is for a single table. There can be many

									# of them.

									tmp_table_size=35M

									# How many threads we should keep in a cache for reuse. When a client

									# disconnects, the client's threads are put in the cache if there aren't

									# more than thread_cache_size threads from before.  This greatly reduces

									# the amount of thread creations needed if you have a lot of new

									# connections. (Normally this doesn't give a notable performance

									# improvement if you have a good thread implementation.)

									thread_cache_size=8

									#*** MyISAM Specific options

									# The maximum size of the temporary file MySQL is allowed to use while

									# recreating the index (during REPAIR, ALTER TABLE or LOAD DATA INFILE.

									# If the file-size would be bigger than this, the index will be created

									# through the key cache (which is slower).

									myisam_max_sort_file_size=100G

									# If the temporary file used for fast index creation would be bigger

									# than using the key cache by the amount specified here, then prefer the

									# key cache method.  This is mainly used to force long character keys in

									# large tables to use the slower key cache method to create the index.

									myisam_sort_buffer_size=69M

									# Size of the Key Buffer, used to cache index blocks for MyISAM tables.

									# Do not set it larger than 30% of your available memory, as some memory

									# is also required by the OS to cache rows. Even if you're not using

									# MyISAM tables, you should still set it to 8-64M as it will also be

									# used for internal temporary disk tables.

									key_buffer_size=55M

									# Size of the buffer used for doing full table scans of MyISAM tables.

									# Allocated per thread, if a full scan is needed.

									read_buffer_size=64K

									read_rnd_buffer_size=256K

									# This buffer is allocated when MySQL needs to rebuild the index in

									# REPAIR, OPTIMZE, ALTER table statements as well as in LOAD DATA INFILE

									# into an empty table. It is allocated per thread so be careful with

									# large settings.

									sort_buffer_size=256K

InnoDB存储引擎使用的参数：

以下是参数的简介：

innodb_additional_mem_pool_size参数表示附加的内存池，用来存储InnoDB表的内容。
innodb_flush_log_at_trx_commit参数是设置提交日志的时机，若设置为1，InnoDB会在每次提交后将事务日志写到磁盘上。
innodb_log_buffer_size参数表示用来存储日志数据的缓存区的大小。
innodb_buffer_pool_size参数表示缓存的大小，InnoDB使用一个缓冲池类保存索引和原始数据。
innodb_log_file_size参数表示日志文件的大小。
innodb_thread_concurrency参数表示在InnoDB存储引擎允许的线程最大数。

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									#*** INNODB Specific options ***

									# Use this option if you have a MySQL server with InnoDB support enabled

									# but you do not plan to use it. This will save memory and disk space

									# and speed up some things.

									#skip-innodb

									# Additional memory pool that is used by InnoDB to store metadata

									# information.  If InnoDB requires more memory for this purpose it will

									# start to allocate it from the OS.  As this is fast enough on most

									# recent operating systems, you normally do not need to change this

									# value. SHOW INNODB STATUS will display the current amount used.

									innodb_additional_mem_pool_size=3M

									# If set to 1, InnoDB will flush (fsync) the transaction logs to the

									# disk at each commit, which offers full ACID behavior. If you are

									# willing to compromise this safety, and you are running small

									# transactions, you may set this to 0 or 2 to reduce disk I/O to the

									# logs. Value 0 means that the log is only written to the log file and

									# the log file flushed to disk approximately once per second. Value 2

									# means the log is written to the log file at each commit, but the log

									# file is only flushed to disk approximately once per second.

									innodb_flush_log_at_trx_commit=1

									# The size of the buffer InnoDB uses for buffering log data. As soon as

									# it is full, InnoDB will have to flush it to disk. As it is flushed

									# once per second anyway, it does not make sense to have it very large

									# (even with long transactions).

									innodb_log_buffer_size=2M

									# InnoDB, unlike MyISAM, uses a buffer pool to cache both indexes and

									# row data. The bigger you set this the less disk I/O is needed to

									# access data in tables. On a dedicated database server you may set this

									# parameter up to 80% of the machine physical memory size. Do not set it

									# too large, though, because competition of the physical memory may

									# cause paging in the operating system.  Note that on 32bit systems you

									# might be limited to 2-3.5G of user level memory per process, so do not

									# set it too high.

									innodb_buffer_pool_size=107M

									# Size of each log file in a log group. You should set the combined size

									# of log files to about 25%-100% of your buffer pool size to avoid

									# unneeded buffer pool flush activity on log file overwrite. However,

									# note that a larger logfile size will increase the time needed for the

									# recovery process.

									innodb_log_file_size=54M

									# Number of threads allowed inside the InnoDB kernel. The optimal value

									# depends highly on the application, hardware as well as the OS

									# scheduler properties. A too high value may lead to thread thrashing.

									innodb_thread_concurrency=18

中文翻译版 my.ini

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									[client]  

									port=3306  

									[mysql]  

									default-character-set=gbk  

									[mysqld]

									port = 3306

									socket = /tmp/mysql.sock

									# 设置mysql的安装目录

									basedir=F:\\Hzq Soft\\MySql Server 51GA

									# 设置mysql数据库的数据的存放目录，必须是data，或者是\\xxx-data

									datadir=F:\\Hzq Soft\\MySql Server 51GA\\data

									#innodb_log_arch_dir 默认datadir

									#innodb_log_group_home_dir  默认datadir

									# 设置mysql服务器的字符集，默认编码

									default-character-set=utf8

									#连接数的操作系统监听队列数量，如果经常出现“拒绝连接”错误可适当增加此值

									back_log = 50

									#不使用接听TCP / IP端口方法，mysqld通过命名管道连接

									#skip-networking

									# 最大连接数量

									max_connections = 90

									#打开表的线程数量限定，最大4096，除非用mysqld_safe打开限制

									table_open_cache = 2048

									#MySql 服务接收针对每个进程最大查询包大小

									max_allowed_packet = 16M

									#作用于SQL查询单笔处理使用的内存缓存，如果一笔操作的二进制数据超过了限定大小，将会在磁盘上开辟空间处理，一般设为 1-2M即可，默认1M

									binlog_cache_size = 2M

									#单个内存表的最大值限定

									max_heap_table_size = 64M

									#为每个线程分配的排序缓冲大小

									sort_buffer_size = 8M

									#join 连表操作的缓冲大小,根据实际业务来设置，默认8M

									join_buffer_size = 32M

									#操作多少个离开连接的线程的缓存

									thread_cache_size = 8

									#并发线程数量，默认为8，可适当增加到2倍以内。如果有多个CPU可以乘 上CPU的数量。双核CPU可以乘 上当前最核数再乘 上70%-85%

									thread_concurrency = 16

									#专用于具体SQL的缓存，如果提交的查询与几次中的某查询相同，并且在query缓存中存在，则直接返回缓存中的结果。

									query_cache_size = 64M

									#对应上一条设置，当查询的结果超过下面设置的大小时，将不会趣入到上面设置的缓存区中，避免了一个大的结果占据大量缓存。

									query_cache_limit = 2M

									#设置加全文检索中的最小单词长度。

									#ft_min_word_len = 4

									#CREATE TABLE 语句的默认表类型，如果不自己指定类型，则使用下行的类型

									default-storage-engine = InnoDB

									#线程堆栈大小，mysql说它自己用的堆栈大小不超过64K。这个值可适当设高一点（在RCA的项目中都是共用同一个数据库连接的），默认192K

									thread_stack = 800K

									#设置事务处理的级别,默认 REPEATABLE-READ，一般用它就即可，以下二行按顺序对应，

									#可读写未提交的数据，创建未提交的数据副本读写，未提交之前可读不可写，只允许串行序列招行事务。

									# READ-UNCOMMITTED, READ-COMMITTED, REPEATABLE-READ, SERIALIZABLE

									transaction_isolation = REPEATABLE-READ

									#单一内存临时表在内存中的大小，超过此值自动转换到磁盘操作

									tmp_table_size = 64M

									#启动二进制日志功能，可通过它实现时间点恢复最新的备份

									#log-bin=mysql-bin

									#二进制日志格式，对就上一条，-建议混合格式

									#binlog_format=mixed

									#转换查询为缓慢查询

									slow_query_log

									#对应上一条，如果一个查询超过了下条设定的时间则执行上一条。

									long_query_time = 2

									#自定义主机ID识别符，用于主从或多服务器之间识别，为 一个 int 类型

									server-id = 1

									#一般用来缓存MyISAM表的主键，也用于临时的磁盘表缓存主键，上面多次出现临时磁盘表，所以就算不用MyISAM也最好为其设置一个不小的值，默认32M

									key_buffer_size = 56M

									#全表扫描MyISAM表时的缓存，每个线程拥有下行的大小。

									read_buffer_size = 2M

									#排序操作时与磁盘之间的缓存，分到每个线程，默认16M

									read_rnd_buffer_size = 16M

									#MyISAM使用特殊树形进行批量插入时的缓存，如insert ... values(..)(..)(..)

									bulk_insert_buffer_size = 64M

									#MyISAM索引文件的最大限定，

									myisam_max_sort_file_size = 12G

									#如果一个myisam表有一个以上的索引， MyISAM可以使用一个以上线程来排序并行它们。较耗硬件资源，如果你的环境不错，可以增加此值。

									myisam_repair_threads = 2

									#自动检查和修复无法正确关闭MyISAM表。

									myisam_recover

									# *** INNODB Specific options ***

									#开启下条将会禁用 INNODB

									#skip-innodb

									#一般不用设置或者说设了也没多大用，InnoDB会自己与操作系统交互管理其附加内存池所使用InnoDB的存储数据的大小

									innodb_additional_mem_pool_size = 16M

									#innodb整体缓冲池大小，不宜过大，设为本地内存的 50%-75% 比较合适,在本机开发过程中可以设得较小一点如 64M,256M

									innodb_buffer_pool_size = 256M

									#InnoDB的数据存储在一个或多个数据文件组成的表空间

									innodb_data_file_path = ibdata1:10M:autoextend

									#用于异步IO操作的线程数量，默认为 4 ，可适当提高

									innodb_file_io_threads = 8

									#线程数内允许的InnoDB内核,不宜太高

									innodb_thread_concurrency = 14

									#InnoDB的事务日志快存行为,默认为 1，为0可减轻磁盘I/0操作，还有以为2

									innodb_flush_log_at_trx_commit = 1

									#InnoDB的用于的缓冲日志数据的大小

									innodb_log_buffer_size = 16M

									#日志文件，可设置为25%-90%的总体缓存大小，默认 256M. 修改此项要先删除datadir\ib_logfileXXX

									innodb_log_file_size = 256M

									#日志组数量，默认为3

									innodb_log_files_in_group = 3

									#InnoDB的日志文件位置。默认是MySQL的datadir

									#innodb_log_group_home_dir

									#InnoDB最大允许的脏页缓冲池的百分比，默认90

									innodb_max_dirty_pages_pct = 90

									#事务死锁超时设定

									innodb_lock_wait_timeout = 120

									[client]

									port = 3306

									socket = /tmp/mysql.sock

									# 设置mysql客户端的字符集

									default-character-set=utf8

									[mysqldump]

									quick

									max_allowed_packet = 16M

									[mysql]

									no-auto-rehash

									# Only allow UPDATEs and DELETEs that use keys.

									#safe-updates

									[WinMySQLAdmin]

									# 指定mysql服务启动启动的文件

									Server=F:\\myweb\\MySql Server\\bin\\mysqld.exe