MySQL 日志
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概述:
本章将介绍MySQL数据库中的各种日志,具体内容如下:
MySQL的日志分类;
查询日志:general_log
慢查询日志:log_slow_queries
错误日志:log_error, log_warnings
二进制日志:binlog
中继日志:relay_log
事务日志:innodb_log
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MySQL的日志分类:
★查询日志:general_log
★慢查询日志:log_slow_queries
★错误日志:log_error, log_warnings
★二进制日志:binlog
★中继日志:relay_log
★事务日志:innodb_log
日志相关的参数:
MariaDB [(none)]> SHOW VARIABLES LIKE '%log%'; +-------------------------------------------+--------------------------------------------------------------------------------------------------------------+ | Variable_name | Value | +-------------------------------------------+--------------------------------------------------------------------------------------------------------------+ | aria_checkpoint_log_activity | 1048576 | | aria_log_file_size | 1073741824 | | aria_log_purge_type | immediate | | aria_sync_log_dir | NEWFILE | | back_log | 50 | | binlog_annotate_row_events | OFF | | binlog_cache_size | 32768 | | binlog_checksum | NONE | | binlog_direct_non_transactional_updates | OFF | | binlog_format | STATEMENT | | binlog_optimize_thread_scheduling | ON | | binlog_stmt_cache_size | 32768 | | expire_logs_days | 0 | | general_log | OFF | | general_log_file | centos7.log | | innodb_flush_log_at_trx_commit | 1 | | innodb_locks_unsafe_for_binlog | OFF | | innodb_log_block_size | 512 | | innodb_log_buffer_size | 8388608 | | innodb_log_file_size | 5242880 | | innodb_log_files_in_group | 2 | | innodb_log_group_home_dir | ./ | | innodb_mirrored_log_groups | 1 | | innodb_recovery_update_relay_log | OFF | | innodb_use_global_flush_log_at_trx_commit | ON | | log | OFF | | log_bin | OFF | | log_bin_trust_function_creators | OFF | | log_error | /var/log/mariadb/mariadb.log | | log_output | FILE | | log_queries_not_using_indexes | OFF | | log_slave_updates | OFF | | log_slow_filter | admin,filesort,filesort_on_disk,full_join,full_scan,query_cache,query_cache_miss,tmp_table,tmp_table_on_disk | | log_slow_queries | OFF | | log_slow_rate_limit | 1 | | log_slow_verbosity | | | log_warnings | 1 | | max_binlog_cache_size | 18446744073709547520 | | max_binlog_size | 1073741824 | | max_binlog_stmt_cache_size | 18446744073709547520 | | max_relay_log_size | 0 | | relay_log | | | relay_log_index | | | relay_log_info_file | relay-log.info | | relay_log_purge | ON | | relay_log_recovery | OFF | | relay_log_space_limit | 0 | | slow_query_log | OFF | | slow_query_log_file | centos7-slow.log | | sql_log_bin | ON | | sql_log_off | OFF | | sync_binlog | 0 | | sync_relay_log | 0 | | sync_relay_log_info | 0 | +-------------------------------------------+--------------------------------------------------------------------------------------------------------------+ 54 rows in set (0.00 sec)
查询日志:general_log
★作用:
记录查询语句;
★日志存储位置:
☉文件:file
·general_log_file=HOSTNAME.log (主机名加log的文件)
☉表:table
·mysql.general_log
★相关参数:
general_log={ON|OFF} 默认是OFF
★定义输出位置
log_output={FILE|TABLE|NONE}
注意:
想要永久有效,要写到配置文件当中,但实际工作中,没有特殊要求,一般不建议开启,因为数据库查询非常多,开启会对I/O造成严重的影响。
演示:
1.开启查询日志,设定输出位置为table和file;
MariaDB [hellodb]> SET GLOBAL general_log = ON; # 开启查询日志 MariaDB [mysql]> SET GLOBAL log_output = 'TABLE,FILE'; # 设定输出位置为TABLE和FILE MariaDB [mysql]> SHOW VARIABLES LIKE 'log_output'; # 查看输出位置 +---------------+------------+ | Variable_name | Value | +---------------+------------+ | log_output | FILE,TABLE | +---------------+------------+ 1 row in set (0.01 sec) MariaDB [mysql]> SELECT @@log_output; +--------------+ | @@log_output | +--------------+ | FILE,TABLE | +--------------+ 1 row in set (0.01 sec)
2.执行查询语句,并查看表和文件是否记录相关的数据
MariaDB [hellodb]> SELECT * FROM mysql.general_log; +----------------------------+---------------------------+-----------+-----------+--------------+----------------------------------+ | event_time | user_host | thread_id | server_id | command_type | argument | +----------------------------+---------------------------+-----------+-----------+--------------+----------------------------------+ | 2016-12-01 10:45:23.715603 | root[root] @ localhost [] | 3 | 0 | Query | SELECT * FROM mysql.general_log | | 2016-12-01 10:45:28.195891 | root[root] @ localhost [] | 3 | 0 | Query | select * from students | | 2016-12-01 10:45:36.486132 | root[root] @ localhost [] | 3 | 0 | Query | SELECT @@log_output | | 2016-12-01 10:45:44.909488 | root[root] @ localhost [] | 3 | 0 | Query | SELECT * FROM mysql.general_log | | 2016-12-01 10:46:11.410438 | root[root] @ localhost [] | 3 | 0 | Query | SHOW VARIABLES LIKE 'log_output' | | 2016-12-01 10:46:20.335378 | root[root] @ localhost [] | 3 | 0 | Query | SELECT * FROM mysql.general_log | +----------------------------+---------------------------+-----------+-----------+--------------+----------------------------------+ 6 rows in set (0.00 sec)
# 在数据库目录中可以看到centos.log的文件,就是查询日志的记录文件 [root@centos7 ~]# cd /var/lib/mysql/ [root@centos7 mysql]# ls aria_log.00000001 centos7.log ibdata1 ib_logfile1 mysql performance_schema test ultrax aria_log_control hellodb ib_logfile0 mydb mysql.sock Syslog testdb zabbix # 查看此文件,可以发现我们刚刚执行过的查询语句 [root@centos7 mysql]# cat centos7.log /usr/libexec/mysqld, Version: 5.5.44-MariaDB (MariaDB Server). started with: Tcp port: 3306 Unix socket: /var/lib/mysql/mysql.sock Time Id Command Argument 161201 10:45:23 3 Query SELECT * FROM mysql.general_log 161201 10:45:28 3 Query select * from students 161201 10:45:36 3 Query SELECT @@log_output 161201 10:45:44 3 Query SELECT * FROM mysql.general_log 161201 10:46:11 3 Query SHOW VARIABLES LIKE 'log_output' 161201 10:46:20 3 Query SELECT * FROM mysql.general_log
慢查询日志:log_slow_queries
★慢查询作用
运行时间超出指定时长的查询;
★指定时长参数:
long_query_time
★存储位置:
文件:FILE
表:TABLE,mysql.slog_log
★相关参数
log_slow_queries={ON|OFF} //启用或关闭慢查询
slow_query_log={ON|OFF}
slow_query_log_file=HOSTNAME.log //慢查询文件记录位置
log_output={FILE|TABLE|NONE} //定义查询输出位置
log_slow_filter=admin,filesort,filesort_on_disk,full_join,full_scan,query_cache,query_cache_miss,tmp_table,tmp_table_on_disk //这些慢查询语句会被过滤掉,是不被记录的
log_slow_rate_limit //慢查询日志的速率限制
log_slow_verbosity //是否记录详细格式信息
演示:
1.查看慢查询日志的时长相关参数,并设定时长
MariaDB [hellodb]> SELECT @@long_query_time; # 查看慢查询时长 +-------------------+ | @@long_query_time | +-------------------+ | 10.000000 | +-------------------+ 1 row in set (0.01 sec) MariaDB [hellodb]> SET @@long_query_time =1; # 设定当前会话时长为1s Query OK, 0 rows affected (0.00 sec) MariaDB [hellodb]> SELECT @@long_query_time; +-------------------+ | @@long_query_time | +-------------------+ | 1.000000 | +-------------------+ 1 row in set (0.00 sec)
2.查看慢查询日志的相关参数,并开启慢查询日志
# 查看当前会话中的慢查询相关参数,可以发现log_slow_queries 和slow_query_log 均为OFF MariaDB [hellodb]> SHOW VARIABLES LIKE 'log_slow%'; +---------------------+--------------------------------------------------------------------------------------------------------------+ | Variable_name | Value | +---------------------+--------------------------------------------------------------------------------------------------------------+ | log_slow_filter | admin,filesort,filesort_on_disk,full_join,full_scan,query_cache,query_cache_miss,tmp_table,tmp_table_on_disk | | log_slow_queries | OFF | | log_slow_rate_limit | 1 | | log_slow_verbosity | | +---------------------+--------------------------------------------------------------------------------------------------------------+ 4 rows in set (0.01 sec) MariaDB [hellodb]> SHOW VARIABLES LIKE 'slow%'; +---------------------+------------------+ | Variable_name | Value | +---------------------+------------------+ | slow_launch_time | 2 | | slow_query_log | OFF | | slow_query_log_file | centos7-slow.log | # 慢查询日志文件的记录位置 +---------------------+------------------+ 3 rows in set (0.01 sec) #开启慢查询日志 MariaDB [hellodb]> SET @@GLOBAL.log_slow_queries=ON; Query OK, 0 rows affected, 1 warning (0.00 sec) MariaDB [hellodb]> SET @@GLOBAL.slow_query_log=ON; Query OK, 0 rows affected (0.00 sec)
错误日志:log_error, log_warnings
★记录信息:
mysqld启动和关闭过程 输出的信息;
mysqld运行中产生的错误信息;
event scheduler运行时产生的信息;
主从复制架构中,从服务器复制线程启动时产生的日志;
★参数:
log_error //给定文件直接记录,永久生效要写在配置文件中,默认是启动的
log_warnings={ON|OFF} //警告信息是否记录在错误日志中
演示:
1.开启错误日志,及错误日志文件的记录位置
MariaDB [(none)]> SHOW VARIABLES LIKE 'log_warnings'; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | log_warnings | 1 | +---------------+-------+ 1 row in set (0.00 sec) MariaDB [(none)]> SHOW VARIABLES LIKE 'log_error'; # 默认就已经启动了 +---------------+------------------------------+ | Variable_name | Value | +---------------+------------------------------+ | log_error | /var/log/mariadb/mariadb.log | +---------------+------------------------------+ 1 row in set (0.01 sec)
二进制日志:binlog
★作用:
用于记录引起数据改变或存在引起数据改变的潜在可能性的语句(STATEMENT)或改变后的结果(ROW),也可能是二者混合;
★功用:
“重放”
★记录方式:
binlog_format={STATEMENT|ROW|MIXED}
☉参数:
STATEMENT:语句;
ROW:行(语句影响到的行内容);
MIXED:混编;
★相关命令
☉查看二进制日志文件列表:
SHOW MASTER|BINARY LOGS;
☉查看当前正在使用的二进制日志文件:
SHOW MASTER STATUS;
☉查看二进制日志文件中的事件:
SHOW BINLOG EVENTS [IN 'log_name'] [FROM pos] [LIMIT [offset,] row_count]
★服务器变量:
log_bin=/PATH/TO/BIN_LOG_FILE
指明记录二进制文件的路径,为了数据安全,建议放在不同的存储设备中
sql_log_bin={ON|OFF}
指明是否记录日志于二进制文件中
max_binlog_size=1073741824
二进制日志文件大小的上限值,超过会自动滚动
sync_binlog={1|0}
一旦有事件提交,就立刻从内存中同步到文件中去,建议启用
★mysqlbinlog:客户端命令
★二进制日志事件格式:
演示:
1.查看二进制日志的当前相关参数:
# 可以发现记录二进制文件的路径log_bin为OFF MariaDB [hellodb]> SHOW VARIABLES LIKE 'log_bin'; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | log_bin | OFF | +---------------+-------+ 1 row in set (0.00 sec) # 是否记录二进制文件的参数sql_log_bin为ON,表示开启 MariaDB [hellodb]> SHOW VARIABLES LIKE 'sql_log_bin'; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | sql_log_bin | ON | +---------------+-------+ 1 row in set (0.00 sec)
2.编辑mysql的配置文件/etc.my.cnf,添加启动记录二进制文件路径的参数,然后重启mysql服务器
3.再次查看二进制日志文件的参数,可以发现都为ON
MariaDB [hellodb]> SHOW VARIABLES LIKE 'log_bin'; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | log_bin | ON | +---------------+-------+ 1 row in set (0.02 sec) MariaDB [hellodb]> SHOW VARIABLES LIKE 'sql_log_bin'; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | sql_log_bin | ON | +---------------+-------+ 1 row in set (0.00 sec) #====================================================================================
4.查看二进制文件列表,及产生的二进制文件的个数
# 显示二进制文件列表,二进制文件是滚动的,一旦重启服务器或者执行FLIUSH LOGS都会不断向上累加新的日志文件 MariaDB [hellodb]> SHOW BINARY LOGS; +-------------------+-----------+ | Log_name | File_size | +-------------------+-----------+ | master-log.000001 | 245 | +-------------------+-----------+ 1 row in set (0.01 sec) MariaDB [hellodb]> FLUSH LOGS; Query OK, 0 rows affected (0.02 sec) MariaDB [hellodb]> SHOW BINARY LOGS; +-------------------+-----------+ | Log_name | File_size | +-------------------+-----------+ | master-log.000001 | 1462 | | master-log.000002 | 1964 | +-------------------+-----------+ 2 rows in set (0.00 sec)
# 在数据库目录中可以查看相应的二进制文件 [root@centos7 ~]# cd /var/lib/mysql/ [root@centos7 mysql]# ls aria_log.00000001 centos7.log hellodb ib_logfile0 master-log.000001 master-log.index mysql performance_schema test ultrax aria_log_control centos7-slow.log ibdata1 ib_logfile1 master-log.000002 mydb mysql.sock Syslog testdb zabbix # 记录产生的二进制文件个数 [root@centos7 mysql]# cat master-log.index ./master-log.000001 ./master-log.000002
5.测试二进制文件记录的事件内容
MariaDB [hellodb]> SELECT * FROM courses; +----------+----------------+ | CourseID | Course | +----------+----------------+ | 1 | Hamo Gong | | 2 | Kuihua Baodian | | 3 | Jinshe Jianfa | | 4 | Taijiquan | | 5 | Daiyu Zanghua | | 6 | Weituo Zhang | | 7 | Dagou Bangfa | | 12 | Nagios | | 13 | Puppet | +----------+----------------+ 9 rows in set (0.00 sec) MariaDB [hellodb]> INSERT INTO courses (Course) VALUES ('Zabbix'); Query OK, 1 row affected (0.00 sec) MariaDB [hellodb]> SHOW BINARY LOGS; +-------------------+-----------+ | Log_name | File_size | +-------------------+-----------+ | master-log.000001 | 1462 | | master-log.000002 | 3375 | +-------------------+-----------+ 2 rows in set (0.00 sec) MariaDB [hellodb]> DELETE FROM courses WHERE CourseID=13; Query OK, 1 row affected (0.04 sec) MariaDB [hellodb]> SELECT * FROM courses; +----------+----------------+ | CourseID | Course | +----------+----------------+ | 1 | Hamo Gong | | 2 | Kuihua Baodian | | 3 | Jinshe Jianfa | | 4 | Taijiquan | | 5 | Daiyu Zanghua | | 6 | Weituo Zhang | | 7 | Dagou Bangfa | | 12 | Nagios | | 14 | Zabbix | +----------+----------------+ 9 rows in set (0.00 sec) MariaDB [hellodb]> SHOW BINARY LOGS; +-------------------+-----------+ | Log_name | File_size | +-------------------+-----------+ | master-log.000001 | 1462 | | master-log.000002 | 4993 | +-------------------+-----------+ 2 rows in set (0.00 sec) # 查看当前正在使用的二进制日志文件 MariaDB [hellodb]> SHOW MASTER STATUS; +-------------------+----------+--------------+------------------+ | File | Position | Binlog_Do_DB | Binlog_Ignore_DB | +-------------------+----------+--------------+------------------+ | master-log.000002 | 4493 | | | +-------------------+----------+--------------+------------------+ 1 row in set (0.00 sec) # 查看记录的信息,可以发现只是记录了跟数据发生改变相关的语句,查询语句SELECT不记录; MariaDB [hellodb]> SHOW BINLOG EVENTS IN 'master-log.000002'; +-------------------+------+-------------+-----------+-------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | Log_name | Pos | Event_type | Server_id | End_log_pos | Info | +-------------------+------+-------------+-----------+-------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | master-log.000002 | 4 | Format_desc | 1 | 245 | Server ver: 5.5.44-MariaDB-log, Binlog ver: 4 | | master-log.000002 | 3236 | Query | 1 | 3348 | use `hellodb`; INSERT INTO courses (Course) VALUES ('Zabbix') | | master-log.000002 | 3348 | Xid | 1 | 3375 | COMMIT /* xid=45 */ | | master-log.000002 | 3797 | Query | 1 | 4094 | use `Syslog`; insert into SystemEvents (Message, Facility, FromHost, Priority, DeviceReportedTime, ReceivedAt, InfoUnitID, SysLogTag) values ('Starting Session 45 of user root.', 3, 'centos7', 6, '20161201145001', '20161201145001', 1, 'systemd:') | | master-log.000002 | 4094 | Xid | 1 | 4121 | COMMIT /* xid=48 */ | | master-log.000002 | 4121 | Query | 1 | 4191 | BEGIN | | master-log.000002 | 4191 | Intvar | 1 | 4219 | INSERT_ID=6790 | | master-log.000002 | 4219 | Query | 1 | 4521 | use `Syslog`; insert into SystemEvents (Message, Facility, FromHost, Priority, DeviceReportedTime, ReceivedAt, InfoUnitID, SysLogTag) values ('(root) CMD (/usr/lib64/sa/sa1 1 1)', 9, 'centos7', 6, '20161201145001', '20161201145001', 1, 'CROND[3654]:') | | master-log.000002 | 4521 | Xid | 1 | 4548 | COMMIT /* xid=52 */ | | master-log.000002 | 4548 | Query | 1 | 4619 | BEGIN | | master-log.000002 | 4619 | Query | 1 | 4720 | use `hellodb`; DELETE FROM courses WHERE Course=13 | | master-log.000002 | 4720 | Query | 1 | 4792 | COMMIT | | master-log.000002 | 4792 | Query | 1 | 4863 | BEGIN | | master-log.000002 | 4863 | Query | 1 | 4966 | use `hellodb`; DELETE FROM courses WHERE CourseID=13 | | master-log.000002 | 4966 | Xid | 1 | 4993 | COMMIT /* xid=57 */ | +-------------------+------+-------------+-----------+-------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ # 显示事件从指定的地方开始 MariaDB [hellodb]> SHOW BINLOG EVENTS IN 'master-log.000002' FROM 9191; +-------------------+------+------------+-----------+-------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | Log_name | Pos | Event_type | Server_id | End_log_pos | Info | +-------------------+------+------------+-----------+-------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | master-log.000002 | 9191 | Intvar | 1 | 9219 | INSERT_ID=6802 | | master-log.000002 | 9219 | Query | 1 | 9516 | use `Syslog`; insert into SystemEvents (Message, Facility, FromHost, Priority, DeviceReportedTime, ReceivedAt, InfoUnitID, SysLogTag) values ('Starting Session 48 of user root.', 3, 'centos7', 6, '20161201151001', '20161201151001', 1, 'systemd:') | | master-log.000002 | 9516 | Xid | 1 | 9543 | COMMIT /* xid=96 */ | | master-log.000002 | 9543 | Query | 1 | 9613 | BEGIN | | master-log.000002 | 9613 | Intvar | 1 | 9641 | INSERT_ID=6803 | | master-log.000002 | 9641 | Query | 1 | 9943 | use `Syslog`; insert into SystemEvents (Message, Facility, FromHost, Priority, DeviceReportedTime, ReceivedAt, InfoUnitID, SysLogTag) values ('(root) CMD (/usr/lib64/sa/sa1 1 1)', 9, 'centos7', 6, '20161201151001', '20161201151001', 1, 'CROND[3720]:') | | master-log.000002 | 9943 | Xid | 1 | 9970 | COMMIT /* xid=100 */ | +-------------------+------+------------+-----------+-------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ 7 rows in set (0.00 sec) # 限制显示的行数 MariaDB [hellodb]> SHOW BINLOG EVENTS IN 'master-log.000002' FROM 9191 LIMIT 3; +-------------------+------+------------+-----------+-------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | Log_name | Pos | Event_type | Server_id | End_log_pos | Info | +-------------------+------+------------+-----------+-------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | master-log.000002 | 9191 | Intvar | 1 | 9219 | INSERT_ID=6802 | | master-log.000002 | 9219 | Query | 1 | 9516 | use `Syslog`; insert into SystemEvents (Message, Facility, FromHost, Priority, DeviceReportedTime, ReceivedAt, InfoUnitID, SysLogTag) values ('Starting Session 48 of user root.', 3, 'centos7', 6, '20161201151001', '20161201151001', 1, 'systemd:') | | master-log.000002 | 9516 | Xid | 1 | 9543 | COMMIT /* xid=96 */ | +-------------------+------+------------+-----------+-------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ 3 rows in set (0.00 sec)
6.有的时候我们不需要开启二进制日志的记录功能(如:导入sql脚本文件,会产生大量的语句)可以在当前会话中关掉记录二进制日志的服务,如下:
# 可以在会话中暂时关闭记录数据于二进制日志文件 MariaDB [hellodb]> SET sql_log_bin = OFF; Query OK, 0 rows affected (0.00 sec)
7.我们也可以使用客户端命令mysqlbinlog,执行查看二进制日志的信息
[root@centos7 mysql]# mysqlbinlog master-log.000002 | head -30 /*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=1*/; /*!40019 SET @@session.max_insert_delayed_threads=0*/; /*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0*/; DELIMITER /*!*/; # at 4 #161201 14:32:47 server id 1 end_log_pos 245 Start: binlog v 4, server v 5.5.44-MariaDB-log created 161201 14:32:47 # Warning: this binlog is either in use or was not closed properly. BINLOG ' D8Q/WA8BAAAA8QAAAPUAAAABAAQANS41LjQ0LU1hcmlhREItbG9nAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAvdx/zw== '/*!*/; # at 245 #161201 14:32:49 server id 1 end_log_pos 315 Query thread_id=3 exec_time=0 error_code=0 SET TIMESTAMP=1480573969/*!*/; SET @@session.sql_mode=0/*!*/; SET @@session.auto_increment_increment=1, @@session.auto_increment_offset=1/*!*/; /*!\C latin1 *//*!*/; SET @@session.character_set_client=8,@@session.collation_connection=8,@@session.collation_server=8/*!*/; SET @@session.lc_time_names=0/*!*/; SET @@session.collation_database=DEFAULT/*!*/; BEGIN /*!*/; # at 315 #161201 14:32:49 server id 1 end_log_pos 343 Intvar SET INSERT_ID=6781/*!*/; # 指定从哪个事件开始 [root@centos7 mysql]# mysqlbinlog --start-position 9991 master-log.000002 #从哪个事件开始到哪个事件结束 [root@centos7 mysql]# mysqlbinlog --start-position 13132 --stop-position 13462 master-log.000002 # 指明从什么时间开始 [root@centos7 mysql]# mysqlbinlog --start-datetime "2016-12-01 15:40:01" master-log.000002
8.binlog的其他参数
MariaDB [hellodb]> SHOW VARIABLES LIKE '%binlog%'; +-----------------------------------------+----------------------+ | Variable_name | Value | +-----------------------------------------+----------------------+ | binlog_annotate_row_events | OFF | | binlog_cache_size | 32768 | | binlog_checksum | NONE | | binlog_direct_non_transactional_updates | OFF | | binlog_format | STATEMENT | | binlog_optimize_thread_scheduling | ON | | binlog_stmt_cache_size | 32768 | | innodb_locks_unsafe_for_binlog | OFF | | max_binlog_cache_size | 18446744073709547520 | | max_binlog_size | 1073741824 | # 大小 | max_binlog_stmt_cache_size | 18446744073709547520 | | sync_binlog | 0 | # 从内存同步到文件,建议启用 +-----------------------------------------+----------------------+ 12 rows in set (0.00 sec)
中继日志:relay_log
★作用:
从服务器上记录下来从主服务器的二进制日志文件同步过来的事件;
事务日志:innodb_log
★作用:
事务型存储引擎innodb用于保证事务特性(ACID)的日志文件:
★事务日志包括:
☉重做日志redo
☉回滚日志undo
★事务日志相关配置参数:
innodb_log_files_in_group //一组中有几个文件,默认为2个
innodb_log_group_home_dir //日志目录的存放位置,默认在数据目录中
innodb_log_file_size //日志文件大小
innodb_mirrored_log_groups //镜像日志组