蓟州网站建设,网站开发公司企业,网站模板中文乱码,自己名下房产查询同大多数关系型数据库一样#xff0c;日志文件是MySQL数据库的重要组成部分。MySQL有几种不同的日志文件。通常包括错误日志文件#xff0c;二进制日志#xff0c;通用日志#xff0c;慢查询日志#xff0c;等等。这些日志能够帮助我们定位mysqld内部发生的事件#xff0…同大多数关系型数据库一样日志文件是MySQL数据库的重要组成部分。MySQL有几种不同的日志文件。通常包括错误日志文件二进制日志通用日志慢查询日志等等。这些日志能够帮助我们定位mysqld内部发生的事件数据库性能故障记录数据的变更历史用户恢复数据库等等。本文主要描写叙述错误日志文件。1、MySQL日志文件系统的组成a、错误日志记录启动、运行或停止mysqld时出现的问题。b、通用日志记录建立的client连接和运行的语句。c、更新日志记录更改数据的语句。该日志在MySQL 5.1中已不再使用。d、二进制日志记录全部更改数据的语句。还用于复制。e、慢查询日志记录全部运行时间超过long_query_time秒的全部查询或不使用索引的查询。f、Innodb日志innodb redo log缺省情况下全部日志创建于mysqld数据文件夹中。能够通过刷新日志来强制mysqld来关闭和又一次打开日志文件(或者在某些情况下切换到一个新的日志)。当你运行一个FLUSH LOGS语句或运行mysqladmin flush-logs或mysqladmin refresh时。则日志被老化。对于存在MySQL复制的情形下。从复制server将维护很多其它日志文件被称为接替日志。2、错误日志错误日志是一个文本文件。错误日志记录了MySQL Server每次启动和关闭的具体信息以及运行过程中全部较为严重的警告和错误信息。能够用--log-error[file_name]选项来开启mysql错误日志。该选项指定mysqld保存错误日志文件的位置。对于指定--log-error[file_name]选项而未给定file_name值mysqld使用错误日志名host_name.err 并在数据文件夹中写入日志文件。在mysqld正在写入错误日志到文件时。运行FLUSH LOGS 或者mysqladmin flush-logs时。server将关闭并又一次打开日志文件。建议在flush之前手动重命名错误日志文件之后mysql服务将使用原始文件名称打开一个新文件。下面为错误日志备份方法shell mv host_name.err host_name.err-oldshell mysqladmin flush-logsshell mv host_name.err-old backup-directory3、实战演示#启用错误日志缺省情况下文件名称为 hostname.err#下面2种方式均可进行错误日志的配置--log-errorfile_name #命令行选项(command option)log-errorfile_Name #配置文件(configure file)#查看当前的错误日志配置,缺省情况下位于数据文件夹mysql show variables like ‘log_error‘;----------------------------------------| Variable_name | Value |----------------------------------------| log_error | /var/lib/mysql/SZDB.err |----------------------------------------1 row in set (0.00 sec)#查看当前mysql server错误日志文件SZDB:/var/lib/mysql # tail SZDB.err140906 22:06:45 InnoDB: Completed initialization of buffer pool140906 22:06:45 InnoDB: highest supported file format is Barracuda.140906 22:06:45 InnoDB: Waiting for the background threads to start140906 22:06:46 InnoDB: 5.5.37 started; log sequence number 1605345140906 22:06:47 [Note] Server hostname (bind-address): ‘0.0.0.0‘; port: 3306140906 22:06:47 [Note] - ‘0.0.0.0‘ resolves to ‘0.0.0.0‘;140906 22:06:47 [Note] Server socket created on IP: ‘0.0.0.0‘.140906 22:06:47 [Note] Event Scheduler: Loaded 0 events140906 22:06:47 [Note] /usr/sbin/mysqld: ready for connections.Version: ‘5.5.37-log‘ socket: ‘/var/lib/mysql/mysql.sock‘ port: 3306 MySQL Community Server (GPL)#停止mysqlserverSZDB:~ # service mysql stopShutting down MySQL.... done#使用配置文件来设置log-error參数SZDB:~ # echo log-error/tmp/SZDB.err/etc/my.cnfSZDB:~ # echo skip_opt/etc/my.cnf #加入一个异常參数skip_optSZDB:~ # grep -v ^# /etc/my.cnf[mysqld]sql_modeNO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLESlog-error/tmp/SZDB.errskip_opt#Author : Leshami#Blog :http://blog.csdn.net/leshami#启动mysqlserverSZDB:~ # mysqld_safe --usermysql [1] 7315SZDB:~ # 140907 13:40:33 mysqld_safe Logging to ‘/tmp/SZDB.err‘.140907 13:40:33 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql140907 13:40:33 mysqld_safe mysqld from pid file /var/lib/mysql/SZDB.pid ended[1] Done mysqld_safe --usermysqlSZDB:~ # more /tmp/SZDB.err140907 13:40:33 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql140907 13:40:33 [ERROR] /usr/sbin/mysqld: ambiguous option ‘--skip-opt‘ (--skip-optimizer_prune_level)140907 13:40:33 [ERROR] Aborting #出现错误提示为有歧义的參数实例终止140907 13:40:33 mysqld_safe mysqld from pid file /var/lib/mysql/SZDB.pid ended#改动my.cnf删除skip-opt选项SZDB:~ # vi /etc/my.cnfSZDB:~ # grep -v ^# /etc/my.cnf[mysqld]sql_modeNO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLESlog-error/tmp/SZDB.err#再次启动mysqlserverSZDB:~ # mysqld_safe --usermysql [1] 7511SZDB:~ # 140907 13:43:23 mysqld_safe Logging to ‘/tmp/SZDB.err‘.140907 13:43:23 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysqlSZDB:~ # more /tmp/SZDB.err140907 13:40:33 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql140907 13:40:33 [ERROR] /usr/sbin/mysqld: ambiguous option ‘--skip-opt‘ (--skip-optimizer_prune_level)140907 13:40:33 [ERROR] Aborting#下面内容为正常启动的相关信息140907 13:40:33 mysqld_safe mysqld from pid file /var/lib/mysql/SZDB.pid ended140907 13:43:23 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql140907 13:43:23 [Note] Plugin ‘FEDERATED‘ is disabled.140907 13:43:23 InnoDB: The InnoDB memory heap is disabled140907 13:43:23 InnoDB: Mutexes and rw_locks use GCC atomic builtins140907 13:43:23 InnoDB: Compressed tables use zlib 1.2.3140907 13:43:23 InnoDB: Using Linux native AIO140907 13:43:23 InnoDB: Initializing buffer pool, size 128.0M140907 13:43:23 InnoDB: Completed initialization of buffer pool140907 13:43:23 InnoDB: highest supported file format is Barracuda.140907 13:43:23 InnoDB: Waiting for the background threads to start140907 13:43:24 InnoDB: 5.5.37 started; log sequence number 1620641140907 13:43:25 [Note] Server hostname (bind-address): ‘0.0.0.0‘; port: 3306140907 13:43:25 [Note] - ‘0.0.0.0‘ resolves to ‘0.0.0.0‘;140907 13:43:25 [Note] Server socket created on IP: ‘0.0.0.0‘.140907 13:43:25 [Note] Event Scheduler: Loaded 0 events140907 13:43:25 [Note] /usr/sbin/mysqld: ready for connections.Version: ‘5.5.37-log‘ socket: ‘/var/lib/mysql/mysql.sock‘ port: 3306 MySQL Community Server (GPL)从上面的错误日能够看出。错误日志文件的格式。通常例如以下时间 [错误级别] 错误信息有些日志信息不一定包括错误级别
