sql statement exercise 50 questions (Mysql version)

sql statement exercise 50 questions (Mysql version) Table names and fields –1. Student list Student(s_id,s_name,s_birth,s_sex) -- student number, student name, date of birth, student gender –2. Class Schedule Card Course(c_id,c_name,t_id) --- course number, course name, teacher number –3. Teacher table Teacher(t_id,t_name) - ...

Posted by cosminb on Tue, 26 Apr 2022 22:49:55 +0300

[SQL Basics: getting to know database and SQL] installation and basic introduction notes

This note is the learning content of Alibaba cloud Tianchi Longzhu program SQL training camp. The link is: https://tianchi.aliyun.com/specials/promotion/aicampsql . 1, First knowledge database Database is a data set that can be accessed efficiently by saving a large amount of data and processing it by computer. This data set is called a d ...

Posted by kellog on Tue, 26 Apr 2022 20:02:43 +0300

High availability of database: failover based on master-slave replication

Now let's introduce the construction of high availability architecture of MHA database. First, let's introduce the steps of installing MHA node node on the machine where the three databases are located. First, perl language environment must be installed first. This is the same as normal Java development. JDK must be installed first! So you can ...

Posted by nogeekyet on Tue, 26 Apr 2022 08:36:51 +0300

MySQL index, transaction and storage engine

1, Concept of index ● index is a sorted list in which the index value and the physical address of the row containing the data of this value are stored (similar to the linked list of C language, pointing to the memory address of the data record through a pointer). ● after using the index, you can not scan the whole table to locate the data ...

Posted by Sirus121 on Tue, 26 Apr 2022 02:55:33 +0300

Deploying Mysql 8.0 database in Kubernetes (single node)

System environment: Mysql version: 8.0.19 Kubernetes version: 1.17.4 Operating system version: CentOS 7.8 1, Introduction Mysql is a commonly used relational database. It is often necessary to deploy a set of Mysql for data storage when the project is developed, tested and deployed to the generation environment. Here's how to deploy Mysql ...

Posted by itsjames on Tue, 26 Apr 2022 00:25:10 +0300

How to solve the problem of data flow in the era of pluralism?

Driven by the digital transformation, the value of data, as an important factor of production, has been redefined. More and more enterprises begin to pay attention to the value of data resources.However, with the continuous increase of the amount of data, the continuous enrichment of data types and the gradual increase of application systems, t ...

Posted by glansing on Mon, 25 Apr 2022 09:42:32 +0300

Spring boot integrates sharding JDBC to realize annual database and monthly table

Spring boot integrates sharding JDBC to realize annual database and monthly table (implementation and brief analysis) 1. Preface: This scheme is applicable to the horizontal segmentation of data with high time dependence. If you just meet the requirements, you can take a look at this article. If you do not meet the requirements, you can also ...

Posted by NDF on Mon, 25 Apr 2022 07:15:59 +0300

JDBC learning notes 02 [detailed explanation of ResultSet class, JDBC login case exercise, detailed explanation of PreparedStatement class]

Dark horse programmer - JDBC document (Tencent micro cloud) JDBC notes pdf: https://share.weiyun.com/Kxy7LmRmJDBC learning notes 01 [JDBC quick start, detailed explanation of various classes of JDBC, CRUD exercise of JDBC][day01]JDBC learning notes 02 [detailed explanation of ResultSet class, JDBC login case exercise, detailed explanation of P ...

Posted by lelelow on Mon, 25 Apr 2022 03:04:53 +0300

MySQL log management, backup and recovery of database

Study preparation: first create a table (I use the previous table here) mysql -u root -p create database school; use school; create table class( id int(10) not null, name varchar(20) not null, sex char(2) not null, cardid varchar(20) not null, phone varchar(11), address varchar(50)); desc class; insert into class values ('1','zhangsan', ...

Posted by omniuni on Mon, 25 Apr 2022 00:29:16 +0300

[Mysql] ORDER BY sort and retrieve data

Sorting query results is a very common requirement. We can use the ORDER BY clause to achieve the purpose The ORDER BY clause takes the name of one or more columns and sorts the output accordingly Typically, the columns used in the ORDER BY clause will be the columns selected for display. However, in fact, this is not necessary. It is complet ...

Posted by jbol on Sun, 24 Apr 2022 19:05:29 +0300