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1, Key value design 1. key name design (1) [suggestion]: readability and manageability Prefix the business name (or database name) (to prevent key conflicts) and separate them with colons, such as business name: Table Name: id ugc:video:1 (2) [suggestion]: simplicity On the premise of ensuring semantics, control the length of keys. When the ...

Bigemap offline map publisher for Linux I. environmental inspection Before installing Bigemap Server, you need to install the following dependencies: WgetOpenSSL (optional)DockerDocker Composeunzip Wget, OpenSSL and unzip are all required by the Bigemap Server installation script. Docker and Docker Compose are service running and integr ...

Pre installation instructions Differences between CentOS6 and CentOS7 in MySQL usage: 1. Firewall: 6 yes iptables，7 yes firewalld 2. Command to start the service: 6 yes service，7 yes systemctl Installation of MySQL for Linux 4 major versions of MySQL MySQL Community Server The community version is open source, free to download, but doe ...

catalogue 1, Installing and configuring mysql module 1. Steps to operate mysql in a project 2. Install and configure mysql module (1) Install mysql module (2) Configure mysql module (3) Test whether the mysql module works normally 2, Using MySQL module to operate MySQL database 1. Query data 2. Insert data 3. Update data 4. Delete ...

Python's unique advantages have created a series of test frameworks. In front of these test frameworks, which is better or worse? How to choose? As the saying goes, "there is no best, there is only the most suitable". Today, we will compete with the four mainstream automated testing frameworks frequently used in Python to select the ...

Data filtering This chapter teaches how to combine WHERE clauses to create more powerful and advanced search conditions. We will also learn how to use the NOT and IN operators. Combine WHERE clause Last chapter( MySQL must know and know - Chapter 6 filtering data )All the WHERE clauses introduced in this article use a single condition when f ...

1 Introduction to mybatis 1.1 what is MyBatis MyBatis is an excellent persistence layer framework, semi-automatic ORM It supports custom SQL, stored procedures and advanced mapping. MyBatis eliminates almost all JDBC code, setting parameters and obtaining result sets. MyBatis can configure and map primitive types, interfaces and Java POJO s ...

1, Foreword Ah Chang summarized and recorded here how to build a cluster of redis hash slot partition solutions through docker [3 master and 3 slave] Knowledge involved: redisdocker basic instructionlinuxHash slot partition 2, Theory Before building, you need to know three partition algorithms built in the redis cluster: hash remai ...

For 3.2 Data query - SELECT (single table query, join query, nested query, set query, multi table query) Learning notes; 0. Preface This article is a note on the database query SELECT part edited by Mr. Wang Shan in introduction to database system, which adopts SQL Sever database.All examples in this article will have screenshots of the resul ...

catalogue 1, Create database 1. Grammar 2. Instance 2, Delete database 1. Grammar 2. Instance 3. Delete collection 3, Insert document 1. Insert document 2. Instance 4, Delete document 1. Grammar 2. Instance 5, Update document 1. updata() method 2. Instance 3. save() method 4. Instance 5. More examples 6. Supplementary oper ...