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ubuntu uses apt get to make offline package (take mysql as an example) Recently, I am studying the deployment of engineering software. Although this is the work of operation and maintenance, it is quite interesting. Question: what factors need to be considered in software environment configuration There are two ways ...

Recently, official account official has been merged into one public official account for the company's business needs, that is to say, one official account (mainly fans) should be transferred to another public number. Two According to WeChat specification, the openid of the same user in different official account is different. Our business syst ...

To fully simulate a complete set of consumer + Mgr environment, we may need to configure the following servers:Three serve as the consumer server, and the other three serve as MySQL servers in MGR single master mode. 1, Build Mysql MGR: Download the new version of mysql 8.0.13 wget https://cdn.mysql.com/archives/mysql-8.0/mysql-8.0.13-linux-gl ...

There are two methods for inserting MySQL test data: Select the priority (generate test data in combination with PHP > use stored procedures). Use stored procedures (it is recommended to use this method when the test data is less than 1000) The specific code is as follows: To create a table: 1 mysql> create table TB1( 2 -> id in ...

MyBatis and Oracle,MySql,SqlServer insert data return primary key method MyBatis Oracle MySql SqlServer insert return primary key MyBatis returns an auto increasing primary key when insert ing data. It can be realized through XML configuration, while different configurations of database are different. Let's take a lo ...

Here I choose the official website to download the source package, compile and install Reference 1: when linux is configured, how do you choose to install it by compilation or by yum Reference 2: mysql installation under linux 1, Preparation: Download address on Mysql official website 2, Pit summary: 2.1 about i ...

The so-called index extension refers to that in the secondary index, innodb adds the primary key to the key of the secondary index, which usually leads to good performance and query plan. Index extension can be used for index scanning of ref, range, index ﹣ merge, loose index scanning, join and sorting optimization, ...

Code generator MyBatis plus (MP for short) is an enhancement tool of MyBatis. Based on MyBatis, only enhancements are made and no changes are made to simplify development and improve efficiency. Step demo 1, Add mybatis plus dependency <!--spring-boot web--> <dependency> <groupId>org.springfram ...

Lateral view is used with split, expand and other UDTF to split a row of data into multiple rows. On this basis, the split data can be aggregated. Lateral view first calls UDTF for each row of the original table, and UDTF will split a row into one or more rows. Then lateral view combines the results to produce a virtual table that supports alia ...

The project needs to back up the database regularly. Here are your own operation notes 1. Check the disk space 　　 # df -h Filesystem Size Used Avail Use% Mounted on /dev/vda1 40G 3.6G 34G 10% / tmpfs 16G 0 16G 0% /dev/shm This is my current situation of linux server. I don't know why it's like this (I'm ...