Basic knowledge of MySql database (including workbench)

1 Table and Keys 0 Introduction If you want to add a column to an already built table, you can use the following code: alter table Table name add column Listing varchar(20) not null; This statement will add a column to the existing table, which is at the last column of the table. If we want toUTF-8...

Posted by eheia on Mon, 08 Nov 2021 23:09:04 +0530

Medical database learning Chapter 3

SQL language Create and modify Although I know that a GUI like DataGrid can be completed at the click of a mouse, considering that it is still very unfriendly for the final exam, I still want to talk about this basic operation Creating and deleting databases create database mydb drop database UTF-8...

Posted by courtewing on Tue, 09 Nov 2021 00:16:52 +0530

MHA and cluster fault simulation

preface when building a mysql Cluster, a single master makes master-slave replication, which greatly improves the reading and writing ability of the database, but once a single point of failure occurs, the whole cluster will be paralyzed. Therefore, we usually configure the master to improve tUTF-8...

Posted by anthonyfellows on Tue, 09 Nov 2021 06:52:47 +0530

Installing MySQL 5.7 on ECs CentOS 7.6

1, Download address 1. mysql official download address: 2. Alicloud disk sharing address: 3. Baidu cloud disk address sharing:

Posted by msimonds on Tue, 09 Nov 2021 14:43:48 +0530

MySQL notes - Summary of top problems in grouping (single table for topn, multi table for topn, index for topn)

When there is only one table, the topn problem of obtaining the value of a field Now there is an employee form emp select * from emp; It is required to list the names of the top two highest paid personnel in each department and the top 2 salary select * from emp as e1 where 2>(select count(*) UTF-8...

Posted by itsgood on Wed, 10 Nov 2021 12:23:32 +0530

Recommend a super lightweight KV storage πŸ”₯

Hi (ΰΉ‘β•Ήβ—‘β•ΉοΎ‰ ", gopher himself has recently built a wheel with Go, a super lightweight KV storage engine. Welcome πŸ‘πŸ» Gopher to evaluate.Homepage introduction: (better PC effect) πŸ˜‹)Project address: storage engineData cUTF-8...

Posted by goochy808 on Tue, 08 Mar 2022 11:44:47 +0530

Database foundation 02 - basic SQL query language

Database foundation 02 - basic SQL query language Using MYSQL as an example Thank you for the installation process Rookie tutorial Ps: in the last note, I found that the table provided by MarkDown is really not suitable for this kind of data table, so I used code blocks instead Creation of dataUTF-8...

Posted by live_ex3me on Tue, 08 Mar 2022 14:49:15 +0530

MySQL creates and manages tables

Create and manage tables Basic knowledge Storage of a piece of data Identifier naming rules Data types in MySQL Commonly used Create and manage databases After deletion, it cannot be restored unless there is a backup Create database Method 1: create directly CREATE DATABASE mytest1; Method 2: sUTF-8...

Posted by AlexP on Tue, 08 Mar 2022 16:24:42 +0530

MySQL scheduled backup database (full)

In the process of operating data, it may lead to data errors and even database collapse, and effective scheduled backup can well protect the database. This article mainly describes several methods to backup MySQL database regularly. I The mysqldump command backs up data MySQL provides a convenUTF-8...

Posted by Napper on Wed, 09 Mar 2022 05:16:02 +0530

MySQL notes: Chapter 10_ Create and manage tables

Note: this content is compiled from the MySQL video of Shangshan Silicon Valley Station B >>MySQL video of Shangsi valley station B 1. Basic knowledge 1.1 a data storage process Storing data is the first step in processing data. Only when the data is stored correctly can it be processed and anUTF-8...

Posted by kath421 on Wed, 09 Mar 2022 07:08:33 +0530