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1. Preface In the previous chapter, we explained the manual compilation and installation process of MySQL and related database operation commands (sql statements). This article will introduce the concept and principle of MySQL index and transaction in detail, and initially understand the concept of MySQL database view, and briefly describe th ...

Summary In distributed systems, there are scenarios where a globally unique ID is required. In order to prevent ID conflicts, a 36-bit UUID can be used, but it has some drawbacks. First, it is relatively long, and UUIDs are generally out of order. Sometimes we want to be able to use a simpler ID, and we want IDs to be generated in time order. ...

Question Summary Nginx section Essential Library yum install -y wget vim gcc gcc-c++ zlib-devel pcre-devel openssl-devel Compile Options ./configure --with-http_stub_status_module --prefix=/data/wwwroot/nginx-1.17.1 --user=www --group=www --with-http_ssl_module Matters needing attention To be added start-up .../sbin/nginx Common Errors To be a ...

A few days ago, we need to make a demand: when adding an xml file, we need to add an xml tag with uncertain quantity and the same attribute. If we want to do it in a table, we need to use the same attribute, and use a unified header. The following attribute values just need to be added, deleted, or modified, just like mysql fil ...

1. If you need to find the records with "three" and "cat" in U ﹣ name, please use and condition Select * from [user] where u name like '% 3%' and u name like '% cat%' If you use select * from [user] where u name like '% 3% cat% Although we can search for "tripods", we can't search for "Zhang ...

Why would I choose mysql?Because my server configuration is low and the SqlServer instance in the docker, the running memory of the server should be kept at 2G+, I don't have this condition, it will pop out the error sqlservr: This program requires a machine with at least 2000 megabytes of memory. Listen to my friend that even if your machine i ...

Answer the selected databases are all MySQL. The following answers are not the best answers. If there is the best answer, please leave a message for communication~ Difficulty: simple 175. Combining two tables select p.FirstName,p.LastName,a.City,a.State from Person p left join Address a on p.PersonId=a.PersonId; 176 ...

Environmental Science: CentOS 7,mysql5.7 Summary description: This article mainly describes how to use mysql common functions, such as string correlation function, date format function, calculation function, etc Steps: 1. Mathematical function Functions for mathematical calculation: -- ABS(X):Return X Absolute value sele ...

How to view the file system type of a partition in Linux? Here are several ways to view the file system type of a partition.     1: df -T command view     This is the simplest command. The file system Type is output in the Type column. Only the mounted partition and file system Type can be viewed. As follows:   [root@mylnx008 ~]# df -T /dev/sd ...

CentOS 6.8 configure MySQL to replicate in SSL encryption mode The master-slave replication of MySQL uses plaintext transmission by default, which is not secure. You can configure the master-slave replication to use SSL encryption connection. Configuration on Master 1. Generate key mysql_ssl_rsa_setup --uid=mysql 2. Copy ...