MySQL: Liệt kê các open transactions (InnoDB Plugin)

Trước tiên phải cài đặt common_schema trước, rồi dùng lệnh sau: SELECT * FROM common_schema.innodb_transactions; Kill các transaction đã...

MySQL: List locked transactions using common_schema framework

Show info on locked transactions: mysql> SELECT * FROM common_schema.innodb_locked_transactions; +---------------+---------------------...

MySQL: Detect duplicate keys using common_schema framework

Detect duplicate keys: SELECT redundant_index_name, sql_drop_index FROM redundant_keys; +----------------------+-------------------------...

Nolock on MySQL

SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED ; SELECT * FROM YOURTABLE SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE REA...

MySQL: How to check if a query is using Index

As the screenshot below, use SQLYod execute the query, look at 'Profiler' tab, 'Possible_keys' and 'key' is null, we...

ps_helper: useful for everyday DBA/Developer

ps_helper is a collection of views and procedures against the performance_schema database within MySQL, that can be used to generate extra...

Solving INFORMATION_SCHEMA slowness

http://www.mysqlperformanceblog.com/2011/12/23/solving-information_schema-slowness/ http://www.mysqlperformanceblog.com/2013/12/03/innodb_st...

Show Log Configuration on MySQL

SHOW VARIABLES LIKE '%log%'; MySQL prior to 5.1.0 requires a change to the MySQL my.cnf file and a restart in order to log slow...

MySQL Performance background

Showing running queries in MySQL show processlist; http://www.electrictoolbox.com/show-running-queries-mysql/ List all indexes for MyS...

Using the USER_STATISTICS Tables

Percona Server and MariaDB include additional INFORMATION_SCHEMA tables for object level usage statistics. These were originally created a...