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System Convention Download directory of installation files / opt/software Mysql directory installation location: usr/local/mysql Database save location / data/mysql Log saving location: data/logs/mysql Dependency package required for MySql installation Before installing mysql, you'd better install the dependency package ...

MySQL GROUP BY statement The GROUP BY statement groups the result set based on one or more columns. We can use COUNT, SUM, AVG, and other functions on grouped columns. GROUP BY syntax SELECT column_name, function(column_name) FROM table_name WHERE column_name operator value GROUP BY column_name; Example demonstration T ...

springboot transaction related 1. Enable global transaction support Enable @ EnableTransactionManagement in SpringbootApplication to support @Transactional Enable APO configuration support @ EnableAspectJAutoProxy (exposeProxy = true) to support automatic transaction configuration in aop mode Where exposePorxy defaults to false and is set t ...

Summary Today, I saw the installation image of zstack on the official website, and found that it was released on March 24, 2018. Because the local environment is a test environment, and I haven't tried to upgrade zstack, I plan to upgrade zstack Things to know before upgrading First of all, zstack supports two upgrade methods on the official w ...

Mysql Event scheduling history The current mysql version does not have Event execution history information. In order to check whether the Event is executed normally and the execution result conveniently, the following two steps can be used:   1, Create job execution Event history table CREATE TABLE `mysql`.`t_event ...

3.3.4.2 select a specific line As shown in the previous section, it is easy to retrieve the entire table. As long as the WHERE clause in the statement is omitted SELECT . But usually you don't want to see the whole table, especially when it gets bigger. Instead, you are usually more interested in answering specific qu ...

1. When installing apache, it has been checked that there is no mysql native to centos installed locally. If there is any, it must be uninstalled, or the port may be occupied 2. Prepare mysql installation package (note that when compiling, the compilation of mysql 5.5 and above is different from that of mysql 5.5 and below. 5.5 needs to be comp ...

The principle of MySQL master master synchronization and master-slave synchronization is the same, except that both sides are master-slave roles. Environmental Science Operating system version: CentOS7 64 bitMySQL version: mysql5.6.33Node 1IP: 192.168.1.205 host name: edu-mysql-01Node 2IP: 192.168.1.206 host name: edu-mysql-0 ...

Several ways of Java inserting current time into MySQL and several ways of java time date format: (refer to network resources for information) Several ways of java inserting current time into MySQL The first is to convert the time of type java.util.Date to the time of type java.sql.Date recognized by mysql database Note: ja ...

In the production environment, the ddl execution of mysql does not affect the normal use of online, and the tool Pt online is often used Install Pt Online Install DBI wget http://www.cpan.org/modules/by-module/DBD/DBI-1.634.tar.gztar -xf DBI-1.634.tar.gzcd DBI-1.634/ perl Makefile.PLmake && sudo make install Install ...