读Effective Mysql:optimizing SQL Statements 笔记之SHOW SLAVE STATUS

zhanghong

show master logs;
+---------------+------------+
| Log_name      | File_size  |
+---------------+------------+
| binlog.000011 | 1073742011 |
| binlog.000012 | 1073742164 |
| binlog.000013 | 1073742004 |
| binlog.000014 |  837378217 |
+---------------+------------+

show slave status\G;
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 10.10.10.11
Master_User: repli
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: binlog.000014
Read_Master_Log_Pos: 837395591
Relay_Log_File: relaylog.000037
Relay_Log_Pos: 837395734
Relay_Master_Log_File: binlog.000014
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB: mysql,test,information_schema
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 837395591
Relay_Log_Space: 837395923
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: No
Master_SSL_CA_File:
Master_SSL_CA_Path:
Master_SSL_Cert:
Master_SSL_Cipher:
Master_SSL_Key:
Seconds_Behind_Master: 0
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno: 0
Last_IO_Error:
Last_SQL_Errno: 0
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id: 1

Mysql provides a view of all information pertaining to the status of replication with SHOW SLAVE STATUS
The \G statement terminator for this statement is important for readability, \G will diplay the output of any SQL statement vertically in the mysql client
SHOW SLAVE STATUS displays information about all aspects of replication for the given slave host.Reading the output earlier,you will be able to see what master server the slave is replicating from
The most important components shown in SHOW SLAVE STATUS pertain to files and positions , along with the SQL AND I/O slave thread.These two threads perform the physical work of writing and reading the relay log (the I/0 thread) and applying the new events on the slave(the SQL thread)
http://dev.mysql.com/doc/refman/5.5/en/show-slave-status.html
http://www.alixixi.com/program/a/2011042069789.shtml