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1.1 MySQL 的下载...................................................................................................................1 1.1.1 在 Windows 平台下下载 MySQL..........................................................................2 1.1.2 在 Linux 平台下下载 MySQL ...............................................................................2 1.2 MySQL 的安装...................................................................................................................5 1.2.1 在 Windows 平台下安装 MySQL..........................................................................5 1.2.2 在 Linux 平台下安装 MySQL .............................................................................10 1.3 MySQL 的配置.................................................................................................................11 1.3.1 Windows 平台下配置 MySQL..............................................................................11 1.3.2 Linux 平台下配置 MySQL ...................................................................................22 1.4 启动和关闭 MySQL 服务...............................................................................................22 1.4.1 在 Windows 平台下启动和关闭 MySQL 服务...................................................22 1.4.2 在 Linux 平台下启动和关闭 MySQL 服务 ........................................................23 1.5 小结..................................................................................................................................25 第 2 章 SQL 基础 ............................................................. 26 2.1 SQL 简介..........................................................................................................................26 2.2 (My)SQL 使用入门..........................................................................................................26 2.2.1 SQL 分类...............................................................................................................26 2.2.2 DDL 语句 ..............................................................................................................26 2.2.3 DML 语句..............................................................................................................35 2.2.4 DCL 语句...............................................................................................................50 2.3 帮助的使用......................................................................................................................51 2.3.1 按照层次看帮助...................................................................................................52 2.3.2 快速查阅帮助.......................................................................................................53 2.3.3 常用网址...............................................................................................................54 2.4 小结..................................................................................................................................54 第 3 章 MySQL 支持的数据类型 ................................................. 55 3.1 数值类型..........................................................................................................................55 3.2 日期时间类型..................................................................................................................61 3.3 字符串类型......................................................................................................................68 3.3.1 CHAR 和 VARCHAR 类型...................................................................................69 3.3.2 BINARY 和 VARBINARY 类型...........................................................................69 3.3.3 ENUM 类型...........................................................................................................70 3.3.4 SET 类型................................................................................................................70 3.4 小结..................................................................................................................................71 第 4 章 MySQL 中的运算符 ..................................................... 72 4.1 算术运算符......................................................................................................................72 4.2 比较运算符......................................................................................................................73 4.3 逻辑运算符......................................................................................................................76 4.4 位运算符..........................................................................................................................77 4.5 运算符的优先级..............................................................................................................79 2 4.6 小结..................................................................................................................................80 第 5 章 常用函数............................................................. 81 5.1 字符串函数......................................................................................................................81 5.2 数值函数..........................................................................................................................84 5.3 日期和时间函数..............................................................................................................86 5.4 流程函数..........................................................................................................................90 5.5 其他常用函数..................................................................................................................92 5.6 小结..................................................................................................................................95 第 6 章 图形化工具的使用..................................................... 96 6.1 MySQL Administrator.......................................................................................................96 6.1.1 连接管理...............................................................................................................96 6.1.2 健康检查...............................................................................................................97 6.1.3 备份管理...............................................................................................................99 6.1.4 Catalogs................................................................................................................100 6.2 MySQL Query Brower....................................................................................................101 6.3 phpMyAdmin..................................................................................................................102 6.3.1 数据库管理.........................................................................................................102 6.3.2 数据库对象管理.................................................................................................103 6.3.3 权限管理.............................................................................................................103 6.3.4 导入导出数据.....................................................................................................104 6.4 小结................................................................................................................................106 第 2 部分 开发篇 第 7 章 表类型（存储引擎）的选择............................................ 107 7.1 MySQL 存储引擎概述...................................................................................................107 7.2 各种存储引擎的特性....................................................................................................109 7.2.1 MyISAM ..............................................................................................................110 7.2.2 InnoDB................................................................................................................. 111 7.2.3 MEMORY............................................................................................................116 7.2.4 MERGE................................................................................................................119 7.3 如何选择合适的存储引擎............................................................................................121 7.4 小结................................................................................................................................122 第 8 章 选择合适的数据类型.................................................. 123 8.1 CHAR 与 VARCHAR.....................................................................................................123 8.2 TEXT 与 BLOB..............................................................................................................124 8.3 浮点数与定点数............................................................................................................128 8.4 日期类型选择................................................................................................................130 8.5 小结................................................................................................................................131 第 9 章 字符集.............................................................. 132 9.1 字符集概述....................................................................................................................132 9.2 Unicode 简述..................................................................................................................132 9.3 汉字及一些常见字符集................................................................................................134 9.4 怎样选择合适的字符集................................................................................................135 9.5 MySQL 支持的字符集简介...........................................................................................135 9.6 MySQL 字符集的设置...................................................................................................137 3 9.6.1 服务器字符集和校对规则.................................................................................137 9.6.2 数据库字符集和校对规则.................................................................................138 9.6.3 表字符集和校对规则.........................................................................................138 9.6.4 列字符集和校对规则.........................................................................................139 9.6.5 连接字符集和校对规则.....................................................................................139 9.7 字符集的修改步骤........................................................................................................139 9.8 小结................................................................................................................................140 第 10 章 索引的设计和使用................................................... 141 10.1 索引概述......................................................................................................................141 10.2 设计索引的原则..........................................................................................................142 10.3 BTREE 索引与 HASH 索引........................................................................................143 10.4 小结..............................................................................................................................144 第 11 章 视图.................................................................. 145 11.1 什么是视图..................................................................................................................145 11.2 视图操作......................................................................................................................145 11.2.1 创建或者修改视图...........................................................................................145 11.2.2 删除视图...........................................................................................................147 11.2.3 查看视图...........................................................................................................147 11.3 小结..............................................................................................................................149 第 12 章 存储过程和函数..................................................... 150 12.1 什么是存储过程和函数..............................................................................................150 12.2 存储过程和函数的相关操作......................................................................................150 12.2.1 创建、修改存储过程或者函数.......................................................................150 12.2.2 删除存储过程或者函数...................................................................................154 12.2.3 查看存储过程或者函数...................................................................................155 12.2.4 变量的使用.......................................................................................................157 12.2.5 定义条件和处理...............................................................................................157 12.2.6 光标的使用.......................................................................................................160 12.2.7 流程控制...........................................................................................................161 12.3 小结..............................................................................................................................166 第 13 章 触发器............................................................. 167 13.1 创建触发器..................................................................................................................167 13.2 删除触发器..................................................................................................................170 13.3 查看触发器..................................................................................................................170 13.4 触发器的使用..............................................................................................................172 13.5 小结..............................................................................................................................172 第 14 章 事务控制和锁定语句................................................. 173 14.1 LOCK TABLE 和 UNLOCK TABLE ..........................................................................173 14.2 事务控制......................................................................................................................174 14.3 分布式事务的使用......................................................................................................180 14.3.1 分布式事务的原理...........................................................................................180 14.3.2 分布式事务的语法...........................................................................................181 14.3.3 存在的问题.......................................................................................................182 4 14.4 小结..............................................................................................................................186 第 15 章 SQL 中的安全问题 ................................................... 187 15.1 SQL 注入简介..............................................................................................................187 15.2 应用开发中可以采取的应对措施..............................................................................188 15.2.1 PrepareStatement+Bind-variable .......................................................................188 15.2.2 使用应用程序提供的转换函数.......................................................................188 15.2.3 自己定义函数进行校验...................................................................................189 15.3 小结..............................................................................................................................190 第 16 章 SQL Mode 及相关问题 ................................................ 191 16.1 MySQL SQL Mode 简介..............................................................................................191 16.2 常用的 SQL Mode.......................................................................................................196 16.3 SQL Mode 在迁移中如何使用....................................................................................196 16.4 小结..............................................................................................................................198 第 3 部分 优化篇 第 17 章 常用 SQL 技巧和常见问题............................................. 199 17.1 正则表达式的使用......................................................................................................199 17.2 巧用 RAND()提取随机行...........................................................................................202 17.3 利用 GROUP BY 的 WITH ROLLUP 子句做统计...................................................203 17.4 用 BIT GROUP FUNCTIONS 做统计........................................................................205 17.5 数据库名、表名大小写问题......................................................................................207 17.6 使用外键需要注意的问题..........................................................................................207 17.7 小结..............................................................................................................................209 第 18 章 SQL 优化 ........................................................... 210 18.1 优化 SQL 语句的一般步骤........................................................................................210 18.1.1 通过 show status 命令了解各种 SQL 的执行频率.........................................210 18.1.2 定位执行效率较低的 SQL 语句 .....................................................................211 18.1.3 通过 EXPLAIN 分析低效 SQL 的执行计划： ..............................................211 18.1.4 确定问题，并采取相应的优化措施：...........................................................212 18.2 索引问题......................................................................................................................213 18.2.1 索引的存储分类...............................................................................................213 18.2.2 MySQL 如何使用索引......................................................................................214 18.2.3 查看索引使用情况...........................................................................................218 18.3 两个简单实用的优化方法..........................................................................................219 18.3.1 定期分析表和检查表.......................................................................................219 18.3.2 定期优化表.......................................................................................................220 18.4 常用 SQL 的优化........................................................................................................221 18.4.1 大批量插入数据...............................................................................................221 18.4.2 优化 INSERT 语句...........................................................................................222 18.4.3 优化 GROUP BY 语句.....................................................................................223 18.4.4 优化 ORDER BY 语句：.................................................................................223 18.4.5 优化嵌套查询...................................................................................................224 18.4.6 MySQL 如何优化 OR 条件..............................................................................225 18.4.7 使用 SQL 提示.................................................................................................227 18.5 小结..............................................................................................................................229 5 第 19 章 优化数据库对象..................................................... 230 19.1 优化表的数据类型......................................................................................................230 19.2 通过拆分提高表的访问效率......................................................................................232 19.3 逆规范化......................................................................................................................233 19.4 使用中间表提高统计查询速度..................................................................................234 19.5 小结..............................................................................................................................235 第 20 章 锁问题............................................................. 236 20.1 MySQL 锁概述.............................................................................................................236 20.2 MyISAM 表锁..............................................................................................................236 20.2.1 查询表级锁争用情况.......................................................................................237 20.2.2 MySQL 表级锁的锁模式..................................................................................237 20.2.3 如何加表锁.......................................................................................................238 20.2.4 并发插入（Concurrent Inserts） .....................................................................240 20.2.5 MyISAM 的锁调度...........................................................................................242 20.3 InnoDB 锁问题.............................................................................................................242 20.3.1 背景知识...........................................................................................................242 20.3.2 获取 InnoDB 行锁争用情况............................................................................244 20.3.3 InnoDB 的行锁模式及加锁方法......................................................................246 20.3.4 InnoDB 行锁实现方式......................................................................................249 20.3.5 间隙锁（Next-Key 锁）..................................................................................253 20.3.6 恢复和复制的需要，对 InnoDB 锁机制的影响............................................255 20.3.7 InnoDB 在不同隔离级别下的一致性读及锁的差异......................................260 20.3.8 什么时候使用表锁...........................................................................................262 20.3.9 关于死锁...........................................................................................................262 20.4 小结..............................................................................................................................268 第 21 章 优化 MySQL Server .................................................. 270 21.1 查看 MySQL Server 参数 ...........................................................................................270 21.2 影响 MySQL 性能的重要参数...................................................................................273 21.2.1 key_buffer_size 的设置.....................................................................................273 21.2.2 table_cache 的设置............................................................................................275 21.2.3 innodb_buffer_pool_size 的设置.......................................................................278 21.2.4 innodb_flush_log_at_trx_commit 的设置 .........................................................278 21.2.5 innodb_additional_mem_pool_size 的设置.......................................................279 21.2.6 innodb_lock_wait_timeout 的设置....................................................................279 21.2.7 innodb_support_xa 的设置................................................................................279 21.2.8 innodb_log_buffer_size 的设置.........................................................................279 21.2.9 innodb_log_file_size 的设置.............................................................................280 21.3 小结..............................................................................................................................280 第 22 章 磁盘 I/O 问题....................................................... 281 22.1 使用磁盘阵列..............................................................................................................281 22.1.1 常见 RAID 级别及其特性...............................................................................281 22.1.2 如何选择 RAID 级别.......................................................................................282 22.2 虚拟文件卷或软 RAID...............................................................................................282 22.3 使用 Symbolic Links 分布 I/O....................................................................................282 6 22.4 禁止操作系统更新文件的 atime 属性......................................................................283 22.5 用裸设备（Raw Device）存放 InnoDB 的共享表空间............................................284 22.6 小结..............................................................................................................................284 第 23 章 应用优化........................................................... 285 23.1 使用连接池..................................................................................................................285 23.2 减少对 MySQL 的访问...............................................................................................285 23.2.1 避免对同一数据做重复检索...........................................................................285 23.2.2 使用查询缓存...................................................................................................285 23.2.3 增加 CACHE 层...............................................................................................286 23.3 负载均衡......................................................................................................................287 23.3.1 利用 MySQL 复制分流查询操作....................................................................287 23.3.2 采用分布式数据库架构...................................................................................287 23.4 其他优化措施..............................................................................................................287 23.5 小结..............................................................................................................................288 第 4 部分 管理维护篇 第 24 章 MySQL 高级安装和升级 ............................................... 289 24.1 Linux/UNIX 下的安装.................................................................................................289 24.1.1 安装包比较.......................................................................................................289 24.1.2 安装 RPM 包....................................................................................................290 24.1.3 安装二进制包...................................................................................................290 24.1.4 安装源码包.......................................................................................................291 24.1.5 参数设置方法...................................................................................................291 24.2 源码包安装的性能考虑..............................................................................................293 24.2.1 去掉不需要的模块...........................................................................................293 24.2.2 只选择要使用的字符集...................................................................................293 24.2.3 使用静态编译以提高性能...............................................................................293 24.3 升级 MySQL................................................................................................................294 24.4 MySQL 降级.................................................................................................................295 24.5 小结..............................................................................................................................295 第 25 章 MySQL 中的常用工具 ................................................. 296 25.1 mysql（客户端连接工具）.........................................................................................296 25.2 myisampack（MyISAM 表压缩工具）......................................................................304 25.3 mysqladmin（MySQL 管理工具）.............................................................................306 25.4 mysqlbinlog（日志管理工具）...................................................................................307 25.5 mysqlcheck（MyISAM 表维护工具）.......................................................................312 25.6 mysqldump（数据导出工具）....................................................................................313 25.7 mysqlhotcopy（MyISAM 表热备份工具）................................................................318 25.8 mysqlimport（数据导入工具） ..................................................................................319 25.9 mysqlshow（数据库对象查看工具）.........................................................................320 25.10 perror（错误代码查看工具）...................................................................................322 25.11 replace（文本替换工具） .........................................................................................323 25.12 小结............................................................................................................................324 第 26 章 MySQL 日志 ......................................................... 325 26.1 错误日志......................................................................................................................325 7 26.2 二进制日志..................................................................................................................326 26.2.1 日志的位置和格式...........................................................................................326 26.2.2 日志的读取.......................................................................................................326 26.2.3 日志的删除.......................................................................................................327 26.2.4 其他选项...........................................................................................................330 26.3 查询日志......................................................................................................................330 26.3.1 日志的位置和格式...........................................................................................330 26.3.2 日志的读取.......................................................................................................331 26.4 慢查询日志..................................................................................................................331 26.4.1 文件位置和格式...............................................................................................331 26.4.2 日志的读取.......................................................................................................332 26.4.3 其他选项...........................................................................................................333 26.5 小结..............................................................................................................................333 第 27 章 备份与恢复......................................................... 335 27.1 备份/恢复策略.............................................................................................................335 27.2 逻辑备份和恢复..........................................................................................................335 27.2.1 备份...................................................................................................................335 27.2.2 完全恢复...........................................................................................................336 27.2.3 基于时间点恢复...............................................................................................338 27.2.4 基于位置恢复...................................................................................................338 27.3 物理备份和恢复..........................................................................................................338 27.3.1 冷备份...............................................................................................................339 27.3.2 热备份...............................................................................................................339 27.4 表的导入导出..............................................................................................................341 27.4.1 导出...................................................................................................................342 27.4.2 导入...................................................................................................................345 27.5 小结..............................................................................................................................349 第 28 章 MySQL 权限与安全 ................................................... 350 28.1 MySQL 权限管理.........................................................................................................350 28.1.1 权限系统的工作原理.......................................................................................350 28.1.2 权限表的存取...................................................................................................350 28.2 账号管理......................................................................................................................353 28.3 MySQL 安全问题.........................................................................................................363 28.3.1 操作系统相关的安全问题...............................................................................363 28.3.2 数据库相关的安全问题...................................................................................366 28.4 其他安全设置选项......................................................................................................384 28.4.1 old-passwords.....................................................................................................384 28.4.2 safe-user-create...................................................................................................385 28.4.3 secure-auth .........................................................................................................387 28.4.4 skip-grant-tables.................................................................................................387 28.4.5 skip-network.......................................................................................................388 28.4.6 skip-show-database ............................................................................................388 28.5 小结..............................................................................................................................389 第 29 章 MySQL 复制 ......................................................... 390 8 29.1 安装配置......................................................................................................................390 29.2 主要复制启动选项......................................................................................................394 29.2.1 log-slave-updates................................................................................................394 29.2.2 master-connect-retry...........................................................................................394 29.2.3 read-only ............................................................................................................394 29.2.4 指定复制的数据库或者表...............................................................................396 29.2.5 slave-skip-errors.................................................................................................397 29.3 日常管理维护..............................................................................................................397 29.3.1 查看从服务器状态...........................................................................................398 29.3.2 主从服务器同步维护.......................................................................................399 29.3.3 从服务器复制出错的处理...............................................................................399 29.3.4 log event entry exceeded max_allowed_packet 的处理....................................401 29.3.5 多主复制时的自增长变量冲突问题...............................................................401 29.3.6 查看从服务器的复制进度...............................................................................404 29.4 切换主从服务器..........................................................................................................406 29.5 小结..............................................................................................................................407 第 30 章 MySQL Cluster...................................................... 408 30.1 MySQL Cluster 架构....................................................................................................408 30.2 MySQL Cluster 的配置................................................................................................409 30.2.1 MySQL Cluster 的版本支持 .............................................................................409 30.2.2 管理节点配置步骤...........................................................................................410 30.2.3 SQL 节点和数据节点的配置 ...........................................................................411 30.3 开始使用 Cluster.........................................................................................................412 30.3.1 Cluster 的启动...................................................................................................412 30.3.2 Cluster 的测试...................................................................................................414 30.3.3 Cluster 的关闭...................................................................................................417 30.4 维护 Cluster.................................................................................................................418 30.4.1 数据备份...........................................................................................................418 30.4.2 数据恢复...........................................................................................................419 30.4.3 日志管理...........................................................................................................421 30.5 小结..............................................................................................................................423 第 31 章 MySQL 常见问题和应用技巧 ........................................... 424 31.1 忘记 MySQL 的 root 密码 ..........................................................................................424 31.2 如何处理 MyISAM 存储引擎的表损坏 ....................................................................425 31.3 MyISAM 表超过 4GB 无法访问的问题.....................................................................426 31.4 数据目录磁盘空间不足的问题..................................................................................427 31.4.1 对于 MyISAM 存储引擎的表 .........................................................................427 31.4.2 对于 InnoDB 存储引擎的表............................................................................428 31.5 DNS 反向解析的问题..................................................................................................428 31.6 mysql.sock 丢失后如何连接数据库............................................................................428 31.7 同一台服务器运行多个 MySQL 数据库...................................................................429 31.8 客户端怎么访问内网数据库......................................................................................429 31.9 小结..............................................................................................................................432

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