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1, Basic command 1. Switch database (select) redis has 16 databases by default, and the 0 database is used by default Command for switching data: select number localhost:6379> select 2 OK # Switching succeeded localhost:6379[2]> # 6379 [2] represents the third database 2. set and get methods Command 1: set ...

Modify permissions: Add Account: Add normal users: useradd guest;echo 'guest:123456'|chpasswd Add root user (mentioned above) echo "test:advwtv/9yU5yQ:0:0:,,,:/root:/bin/bash" >>/etc/passwd Account: test Password: password@123 It's easy to add an account to maintain permissions. Defense method: Query Privileged User Privi ...

Title Description Give you an array of rectangles, where rectangles[i] = [xi, yi, ai, bi] represents a rectangle with parallel coordinate axes. The lower left vertex of the rectangle is (xi, yi) and the upper right vertex is (ai, bi). Returns true if all rectangles together exactly cover a rectangular area; Otherwise, false is returned. ...

What is the status bar: It refers to the top left of the mobile phone, showing China Mobile, security guards, power, network speed, etc. at the top of the mobile phone. The drop-down will display the notification bar. Let me show you a picture Immersive status bar: Simply put, the status bar will change color adaptively according to the mob ...

1. Preface Previous: https://blog.csdn.net/ylc0919/article/details/111050124 It's been ten months since I said I would send the second generation framework. It's hard to have time to summarize the harvest during this period. After writing the first generation AT queue, I have many ideas. For example, can one AT queue manage multiple AT mod ...

Basic overview of object oriented Object oriented programming (OOP): more extensible and readable. Object oriented programming encapsulates data and operation data into objects. The way of organizing code and data is closer to human thinking and improves programming efficiency.python supports many programming paradigms such as object-oriented, ...

               When you want to update your Web application in real time, you can rely on old-fashioned periodic polling or try some modern technology with push function. Your first impulse may be to use WebSockets . However, if you only want to receive data from the server, you can use Server Sent Events. Traditionally, web pages ...

2021SC@SDUSC Let's analyze the details of outbound data propagation. Let's start with the write method of ChannelOutboundHandlerAdapter: public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception { ctx.write(msg, promise); } If you want to implement your own business processing logic, ...

preface    the deadlock problem in the case of HashMap concurrency exists in jdk 1.7 and before. jdk 1.8 has been repaired by adding loHead and loTail. Although it has been repaired, if concurrency is involved, it is generally recommended to use CurrentHashMap instead of HashMap to ensure that thread safety problems will not o ...

1, ES5 (ECMAScript version 5) 1. Add a function in the array Judgment function          every() is used to judge whether all elements in an array meet the requirements. The format is as follows: var Judgment result=array.every( function(Current element value n,Current subscript i,Current array ...