Notes on Mybatis source code: from the perspective of cache system, the distribution mode of responsibility chain and enterprise level practice of circular dependence
1, Cache overview
The design of Mybatis cache system follows the principle of single responsibility, opening and closing, and high decoupling. It is exquisite and fully layered, and its unique features can be applied to many similar businesses. Here is a brief analysis of the main caching system. With the help of the learning of Mybatis cache ...
Added by php_b34st on Tue, 16 Jun 2020 11:41:24 +0300
Stored procedure cursor
example:
At present, there are three tables A, B and C. among them, A and B are one to many relationships, and B and C are one to many relationships. Now it is necessary to save the primary key of table A in B into C;
The general idea is to query out B and update table C with an update statement, bu ...
Added by bobicles2 on Tue, 16 Jun 2020 10:41:40 +0300
django Series 5 - QuerySet API operation
QuerySet API usage
QuerySet can construct, filter, slice, and approximate results without actually accessing the database. Unless you do something to evaluate the query set, no query activity actually occurs to the database.
(1) Basic properties
iteration
The QuerySet is iterative, and its databa ...
Added by Phire on Tue, 16 Jun 2020 06:59:36 +0300
Method of Using Redis to Count Web UV s
Article Directory
Preface
thinking
HyperLogLog
Use Redis command action
Working with Java code
The Principle and Feature of HyperLog Implementation
Implement HyperLog using Java
Summary
Preface
Web site UV refers to the amount of Unique Visitor visited by independent users of a Web site, that ...
Added by BlueSkyIS on Tue, 16 Jun 2020 03:56:18 +0300
Spring Boot Task Scheduling
2.1.12 Timing Tasks
The Spring framework comes with task scheduling capabilities that are like a lightweight Quartz and are easy to use without relying on other JAR packages.
Simply add @EnableScheduling to the project master startup class to turn on task scheduling
@SpringBootApplication
@EnableScheduling
public class LearnApplication {
p ...
Added by Desbrina on Mon, 15 Jun 2020 21:10:56 +0300
jdbc advanced custom connection pool and custom jdbc framework
JDBC advanced
Use of JDBC connection pool
The concept of database connection pool
Database connection is a key and limited resource. When java program and database get the connection, it consumes resources especially. Therefore, a database connection pool is created to manage the connection betwe ...
Added by shane0714 on Mon, 15 Jun 2020 11:47:18 +0300
SQL Server advanced query and T-SQL programming and transaction DQL+DML+DDL+DCL to realize warehouse inventory management system (example code display)
SQL Server advanced query and T-SQL programming to realize warehouse inventory management system
SQL Server advanced query and T-SQL programming
SQL Server advanced query and T-SQL programming to realize warehouse inventory management system
1. Language and environment
2. Functional requirements
3 ...
Added by bleh on Sat, 13 Jun 2020 09:21:58 +0300
LAMP builds forum and blog platform
Article catalog
What is LAMP
Build Forum
Build a blog
What is LAMP
LAMP refers to Linux (operating system) + Apache (HTTP server) + MySQL/MariaDB (database) and PHP (network programming language), which are generally used to build a web application platform.
Build Forum
1. First, make sure you ...
Added by V34 on Sat, 13 Jun 2020 08:39:11 +0300
Detailed process of springboot framework building
1. Create
1.1 Create a new springboot project, as shown in the figure.
1.2 Select Spring Initializr.
1.3 Fill in Group, Artifact, and Name, where you choose the default, then click next, as shown in the following image.
1.4 Choose the components you want: The basic components are the web and web s ...
Added by Jax2 on Thu, 11 Jun 2020 19:19:20 +0300
Distributed Lock+Redis for Cluster Business Data Caching
Article Directory
Distributed Lock
1. Distributed Lock Implementation
2. Distributed Lock Using redis
Learning optimization
summary
Problems in the redis cluster state:
Solving distributed locks using redisson
1. Import dependent service-util
2. Configure redisson
Reentrant Lock
Test Code
Dis ...
Added by dev99 on Wed, 10 Jun 2020 19:17:31 +0300