[original] CentOS 7 builds multiple instances of MySQL 8 (want to do several)

cause   Recently, the project began to be reconstructed, which may use the situation that the master-slave plus read-write separation. I wanted to build a local one first to try the effect. As a result, baidu found a lot of them, but few of them went to the pit. Most of them were copying other people's content. The key is that there will be e ...

Posted by windjohn on Mon, 25 May 2020 21:57:20 -0700

20. Use and principle of PageHelper paging plug-in

1. Logical paging and physical paging Logical paging: also called memory paging. Logical paging depends on the code written by the programmer. What the database returns is not the paging result, but all the data, which is then passed by the programmer The code obtains the paging data, takes out all the data, first stores it in memory, ...

Posted by ChetUbetcha on Mon, 25 May 2020 20:53:31 -0700

MySQL installation and basic use under Linux

1. MySQL installation (install using yum) yum install mysql* –y Linux MySQL data is stored in / var/lib/mysql by default/ [root@study ~]# cd /var/lib/mysql/ [root@study mysql]# ll //Total consumption 20488 -rw-rw----. 1 mysql mysql 10485760 5 23 23:55 ibdata1 -rw-rw----. 1 mysql mysql 5242880 5 23 23:55 ib_logfile0 -rw-rw----. 1 mysql mysql 5 ...

Posted by Exemption on Sun, 24 May 2020 22:31:29 -0700

The last packet sent successfully to the server was 1 milliseconds ago.

Weird database exception: There are mainly two abnormal sections as follows 1. Connection reset The last packet successfully received from the server was 1 milliseconds ago. The last packet sent successfully to the server was 1 milliseconds ago. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.Na ...

Posted by TFD3 on Fri, 22 May 2020 08:03:25 -0700

Spring boot from scratch integrates spring data JPA to realize simple application

This paper introduces the simple application of spring boot integrating spring data JPA What is spring data jpa? We can't help thinking about it. In fact, spring data jpa uses hibernate by default and spring data jpa technology, which implements the template Dao layer. It only needs to inherit an interface in Dao to easily complete "add, d ...

Posted by k4pil on Fri, 22 May 2020 02:53:32 -0700

DELETE_ DROP_ Research on record content of truncate command in binlog of ROW format

Today, a question suddenly comes to mind. Is the DELETE, DROP, TRUNCATE command the same as the binlog in ROW format? It's not the same to remember vaguely, but it's not sure; so let's take a look at the experiment. MySQL:5.6.20MySQL:5.7.22 1. View binlog settings mysql> show variables like 'binlog_format'; +---------------+-------+ | Vari ...

Posted by rharter on Wed, 20 May 2020 08:33:53 -0700

Develop blog project based on abp vNext and. NET Core - data access and code first

Last article( https://www.cnblogs.com/meowv/p/12909558.html )Improved the code in the project and connected to Swagger. This article mainly uses the Entity Framework Core to access the database, and uses the code first method for data migration and automatic creation of table structure. data access Add our data access context object MeowvBl ...

Posted by Monshery on Wed, 20 May 2020 02:56:28 -0700

Using Nginx to record and display the TOP 20 Web interface with slow response

I believe that many small partners have seen the response time and real-time display function of url interface in some commercial products. It can be understood that the slow query of web interface and the slow query of sql have the same magic, but if you want to do it, you have no way to start and don't know how to realize this function, so to ...

Posted by Jak on Mon, 18 May 2020 23:19:14 -0700

Log mysql operations

Now I want to compare the differences before and after php web page execution, but I still can't find better software Add, delete, and change the kind that is recorded. Then MySQL 5 is discovered by browsing the official documentation.1 has one Common Query Log .So try: #cd /Applications/XAMPP/xamppfiles/bin cd /Appl ...

Posted by Goofan on Fri, 15 May 2020 09:17:40 -0700

On Redis basic type Hash

Redis has five basic types: string, list, Hash, set and sorted set. This time, the common operations of Hash are listed. Redis official website: https://redis.io/    1, Hash introduction Hash is the basic type in Redis. A key corresponds to a set, in which a dictionary is formed in the form of field value. It can be understood that in a di ...

Posted by bmpco on Wed, 13 May 2020 18:07:39 -0700