Pitfalls encountered in Mysql
Pitfalls encountered in Mysql
1. Erdog, when you create a table, do you always set Null as the default value?
Damn, how do you know, how simple Null is, how convenient it is to set Null without passing a value, and it doesn’t take up much space, and you don’t need to fill in the code, and you don’t need to judge.
Ergou, ...
Posted by onion2k on Sun, 20 Nov 2022 01:41:10 +0300
cocos creator deploys WeChat cloud development
Hello everyone, we meet again, I am your friend Quanzhangjun.
(This is just my little brother's study notes, not a tutorial, if there are any mistakes, please point them out)In cocos creator, by calling WeChat The interface to obtain user authorization information, and then the cloud function saves the user data to the cloud database, ...
Posted by davex on Thu, 17 Nov 2022 09:59:02 +0300
[Akka] Akka concurrent programming design
1 Overview
Reprinted: Akka concurrent programming design
2. Responsive system design
Akka is known to be a reactive platform, more specifically, it is part of the Typesafe reactive platform. The Reactive Manifesto contains 4 principles or design goals: agility, scalability, fault tolerance, and event-driven design.
Sensitivity
Applicatio ...
Posted by MBK on Sun, 13 Nov 2022 12:52:20 +0300
MongoDB tool commands and user authentication
1.MongoDB tool command
1.1.Mongod command
MongoDB is the main daemon of the MongoDB system. It handles data requests, manages data access, and performs background management operations. The startup process specifies a configuration file that controls database behavior.
1.2.Mongos command
For "MongoDB Shard", Mongos is a routin ...
Posted by logging on Thu, 10 Nov 2022 21:51:01 +0300
[Redis] Redis basics of redis learning
This article is mainly to learn Dark horse programmer Redis entry to actual combat tutorial, in-depth analysis of the underlying principle of redis + redis distributed lock + enterprise solution + dark horse comment on the actual project income from
1 Introduction to Redis
Redis is a key-value NoSql database. The key-value type means ...
Posted by Bulbe on Wed, 09 Nov 2022 20:22:25 +0300
Java uses tool classes to improve the efficiency of writing reports
The tool class and demo code repository in this article
Why use java code to write reports
For report data, in most cases, the method of writing sql is used to provide data sources for large screens/reports, but in some complex cases, it cannot be achieved by using only sql, or when it is difficult to achieve, it will be adopted to implement ...
Posted by patrickcurl on Sun, 23 Oct 2022 01:29:01 +0300
A Java-based Accounting Management System Completed by Computer
Code + paper download link:
http://106.55.47.97/host-pictures/java.png
Overview
The Java accounting management system is mainly used for financial personnel to judge the development direction of the company from the accounts. For individuals and families, future consumption plans can be formulated through bookkeeping, so as to draw a clear ...
Posted by dotnotwhat on Sat, 22 Oct 2022 22:56:11 +0300
Redis installation and startup (the latest nanny tutorial in 2022)
Redis installation and startup
Redis official website address: https://redis.io/
1. Install Redis on a single machine
1.1. Install Redis dependencies
Redis is written based on the C language, so first you need to install the gcc dependencies required by Redis:
yum install -y gcc tcl
1.2. Upload the installation package and extract it
If ...
Posted by David Rech on Sun, 16 Oct 2022 01:32:58 +0300
Detailed explanation of Redis caching problems
cache penetrationCache penetration means that the data requested by the client does not exist in the cache and the database, so the cache will never take effect, and these requests will hit the databaseIf a malicious user uses countless threads to concurrently access non-existent data, these requests will all reach the database, which is likely ...
Posted by bliss322 on Sun, 25 Sep 2022 21:01:59 +0300
Redis advanced practice
Redis advanced practice
transaction management
Comparison between redis and mysql redis slow log queryredis high availability and cluster
redis master-slave replication
Synchronization mechanism**Master slave replication principle****Command propagation**SYNC and PSYNCConsistency of redis replication ...
Posted by ben2.0 on Sat, 27 Aug 2022 14:01:57 +0300