Original address: https://mysqlserverteam.com/mysql-explain-analyze/
MySQL 8.0.18 was just released. October 17, 2019 ), which includes a new feature to analyze and understand how queries are executed: explain analyze.
What is explain analyze
EXPLAIN ANALYZE is a query analysis tool that tells you how much time MySQL spends on queries and why ...
Added by dw89 on Fri, 29 May 2020 19:45:52 +0300
Chapter 0 of MySql, installation and cluster configuration
1, MySql installation
1. RPM installation
RPM installation, unable to customize some installation paths and configuration file paths
##Fill in the pit later
2. Generic installation
Binary precompiled Generic, download address:
Added by khendar on Tue, 26 May 2020 17:54:42 +0300
Ccom.mysql.cj.jdbc.exceptions.MySQLTransactionRollbackException: Lock wait timeout exceeded; try restarting transaction
Reasons for the problem
When optimistic locks modify data, the data version number has been modified, causing the modification to fail. When retrying the modification, each time the data read from the d ...
Added by xsist10 on Fri, 22 May 2020 21:51:58 +0300
JDBC fixing steps:
Class.forName("com.mysql.cj.jdbc.Driver");//I don't know why com.mysql.jdbc.Driver will report an error. Please leave a message if you have any ...
Added by PHPfolife on Wed, 20 May 2020 17:31:54 +0300
In Oracle and SQL Server databases, you can set up some complex account password policies, such as locking an account more than N times after a failed login, so can you do the same in MySQL?The answer is that MySQL has similar capabilities, except in MySQL it delays the response time when its login fails beyond the threshold, instead of locking ...
Added by marco839 on Tue, 19 May 2020 20:23:28 +0300
We have learned about Spring Cloud Config before:
Consul configuration center of Spring Cloud series (I)
Consul configuration center of Spring Cloud series (2)
Consul configuration center of Spring Cloud series (3)
It provides the function of configuration center, but it needs to cooperate with git, svn or external storage (such as various da ...
Added by synergypoint on Mon, 18 May 2020 09:51:39 +0300
1, Date and time functions
1. Function to get the current dateIt's the same. It's different
CURDATE() : Used to get the current date of the system
CURRENT_DATE() Used by the system to get the current date
mysql> select CURDATE(),CURRENT_DATE();
2. Get function of current time
CURTIME() : Used to get the current time of the system
Added by brighton on Thu, 14 May 2020 12:11:49 +0300
Use Prometheus and Grafana to monitor MySQL server performance.Use two exporter s:Node? Exporter: server system data collectionmysqld_exporter: MySQL server data collectionMonitoring architecture:
Prometheus installation configurationInstallation mode binary installation, see here for details CentOS7 deployment PrometheusVersion: current late ...
Added by dhruvasagar on Thu, 14 May 2020 02:15:46 +0300
check constraint means to filter one or more columns according to certain preset rules. If the condition is true, the filtering succeeds; if the condition is false, the filtering fails and the failure code is returned to the client.
Why do you want to list and write this separately? You often encounter irregular SQL. In many cases, you can onl ...
Added by AndyB on Wed, 13 May 2020 12:25:22 +0300
Original address: https://mysqlserverteam.com/mysql-8-0-innodb-now-supports-instant-add-column/
For a long time, instant DDL has been one of the most popular InnoDB functions. For the growing and fast-growing data set, any network scale database must have the function of executing DDL immediately.
Developers often need to add new columns to m ...
Added by coolfool on Tue, 12 May 2020 16:55:02 +0300