15 practical examples of using commands Mysqladmin to administer a MySQL server Wednesday, 17 March :23

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1 In the 15 examples of the use mysqladmin command below, using the password root Mysql tmppassword. Change it to your password 1. How to change the root password for Mysql? # mysqladmin -u root -ptmppassword password 'newpassword' # mysql -u root -pnewpassword Welcome to the MySQL monitor. Commands end with ; or g. Your MySQL connection id is 8 Server version: rc-community MySQL Community Server (GPL) Type 'help;' or 'h' for help. Type 'c' to clear the buffer. mysql> 2. How to check whether the MySQL server is running using # mysqladmin -u root -p ping Enter password: mysqld is alive 3. How do I see what version of MySQL is running using This command also displays the current status of the server. # mysqladmin -u root -ptmppassword version mysqladmin Ver 8.42 Distrib rc, for redhat-linux-gnu on i686 Copyright (C) MySQL AB This software comes with ABSOLUTELY NO WARRANTY. This is free software, and you are welcome to modify and redistribute it under the GPL license Server version rc-community Protocol version 10 Connection Localhost via UNIX socket UNIX socket /var/lib/mysql/mysql.sock Uptime: 107 days 6 hours 11 min 44 sec Threads: 1 Questions: Slow queries: 0 Opens: Flush tables: 1 Open tables: 64 Queries per second avg: How to see the status of the MySQL server using 1 / 7

2 # mysqladmin -u root -ptmppassword status Uptime: Threads: 1 Questions: Slow queries: 0 Opens: Flush tables: 1 Open tables: 64 Queries per second avg: 0.25 Status command displays the following informatsiyucommand displays the following information: - Uptime: uptime in seconds - Threads: Total number of clients connected to the server. - Questions: The total number of requests to the server since startup. - Slow queries: Total number of queries, whose execution time was more than the value of long_query_time. - Opens: Total number of tables opened by the server. - Flush tables: How many times the tables were flushed. - Open tables: Total number of open tables in the database. 5. How do I view MySQL status variables and their current value using # mysqladmin -u root -ptmppassword extended-status Variable_name Value Aborted_clients 579 Aborted_connects 8 Binlog_cache_disk_use 0 Binlog_cache_use 0 Bytes_received Bytes_sent Com_admin_commands 3524 Com_assign_to_keycache 0 Com_alter_db 0 Com_alter_db_upgrade 0 6. How to display all the MySQL server system variables and their values using # mysqladmin -u root -ptmppassword variables Variable_name Value auto_increment_increment 1 2 / 7

3 basedir / big_tables OFF binlog_format MIXED bulk_insert_buffer_size character_set_client latin1 character_set_database latin1 character_set_filesystem binary skip... time_format %H:%i:%s time_zone SYSTEM timed_mutexes OFF tmpdir /tmp tx_isolation REPEATABLE-READ unique_checks ON updatable_views_with_limit YES version rc-community version_comment MySQL Community Server (GPL) version_compile_machine i686 version_compile_os redhat-linux-gnu wait_timeout How to display all running processes / queries in the database mysql using # mysqladmin -u root -ptmppassword processlist 20 root localhost Sleep root localhost Query 0 show processlist You can use this command to effectively debug any performance problems and determine the process that causes problems by running on autoupdate every second. # mysqladmin -u root -ptmppassword -i 1 processlist 20 root localhost Sleep root localhost Query 0 show processlist 3 / 7

4 24 root localhost Query 0 show processlist 8. How to create database a MySQL using # mysqladmin -u root -ptmppassword create testdb # mysql -u root -ptmppassword Welcome to the MySQL monitor. Commands end with ; or g. Your MySQL connection id is 705 Server version: rc-community MySQL Community Server (GPL) Type 'help;' or 'h' for help. Type 'c' to clear the buffer. mysql> show databases; Database information_schema mysql sugarcrm testdb rows in set (0.00 sec) Note: To display all the tables in the database, the total number of columns, rows, indexes and so on... use the command mysqlshow. 9. How do I delete the existing database MySQL using # mysqladmin -u root -ptmppassword drop testdb Dropping the database is potentially a very bad thing to do. Any data stored in the database will be destroyed. Do you really want to drop the 'testdb' database [y/n] y Database testdb dropped # mysql -u root -ptmppassword Welcome to the MySQL monitor. Commands end with ; or g. Your MySQL connection id is 707 Server version: rc-community MySQL Community Server (GPL) Type help; or h for help. Type c to clear the buffer. mysql> show databases; + + Database + + information_schema mysql sugarcrm rows in set (0.00 sec) 4 / 7

5 10. How to overload all the privileges and rights to the table using # mysqladmin -u root -ptmppassword reload; Refresh command resets the table and close / open the log files. # mysqladmin -u root -ptmppassword refresh 11. How to perform a safe way to stop MySQL server using # mysqladmin -u root -ptmppassword shutdown # mysql -u root -ptmppassword ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' You can use the command "/ etc / rc.d / init.d / mysqld stop" to stop the server. To start the run "/ etc / rc.d / init.d / mysql start" 12. List of all mysqladmin flush commands. # mysqladmin -u root -ptmppassword flush-hosts # mysqladmin -u root -ptmppassword flush-logs # mysqladmin -u root -ptmppassword flush-privileges # mysqladmin -u root -ptmppassword flush-status # mysqladmin -u root -ptmppassword flush-tables # mysqladmin -u root -ptmppassword flush-threads - Flush-hosts: Reset all the information in the cache hosts. - Flush-privileges: Reload right. - Flush-status: Clear status variables. - Flush-threads: Flush the thread cache. 13. How to kill hung client process to MySQL using First, define the hanging process using the command processlist. # mysqladmin -u root -ptmppassword processlist 20 root localhost Sleep root localhost Query 0 show processlist 5 / 7

6 Then use the kill command and the desired process_id. To complete several processes separate process id commas. # mysqladmin -u root -ptmppassword kill 20 # mysqladmin -u root -ptmppassword processlist 26 root localhost Query 0 show processlist 14. How to start or stop the replication of MySQL on the slave-server using # mysqladmin -u root -ptmppassword stop-slave Slave stopped # mysqladmin -u root -ptmppassword start-slave mysqladmin: Error starting slave: The server is not configured as slave; fix in config file or with CHANGE MASTER TO 15. How to combine several commands mysqladmin together? In the example below combined team process-list, status and version for the complete withdrawal of the status of the server. # mysqladmin -u root -ptmppassword process status version 43 root localhost Query 0 show processlist Uptime: 3135 Threads: 1 Questions: 80 Slow queries: 0 Opens: 15 Flush tables: 3 Open tables: 0 Queries per second avg: 0.25 mysqladmin Ver 8.42 Distrib rc, for redhat-linux-gnu on i686 Copyright (C) MySQL AB This software comes with ABSOLUTELY NO WARRANTY. This is free software, and you are welcome to modify and redistribute it under the GPL license Server version rc-community Protocol version 10 Connection Localhost via UNIX socket UNIX socket /var/lib/mysql/mysql.sock Uptime: 52 min 15 sec 6 / 7

7 You can also use the short form of writing: # mysqladmin -u root -ptmppassword pro stat ver Use the-h option to connect to remote MySQL server and execute the command. # mysqladmin -h u root -ptmppassword pro stat ver Useful articles: Mysqladmin is a client for performing administrative operations! Leave a comment! {jcomments on} 7 / 7