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Originally, I was going to go directly to the actual combat. Later, I thought, I'd better finish the necessary things first. Otherwise, many things in the actual combat will be confused and it will be troublesome to talk recursively. This article is the last content explanation of pandas. The three connected together should be enough to deal w ...

Subquery refers to a query in which one query statement is nested inside another query statement. This feature has been introduced since MySQL 4.1. The use of SQL sub query greatly enhances the ability of SELECT query, because many times the query needs to obtain data from the result set, or calculate a data result from the same table, an ...

1, Introduction Message queue functions: decoupling, asynchronous and peak clipping Why use message queuing? What are the benefits of messages for columns- Laughing Terry - blog Gardenhttps://www.cnblogs.com/terry-love/p/11492397.html 2, RabbitMQ introduction Several popular MQ models in the market: ActiveMQ，RocketMQ，Kafka，RabbitMQ ...

Apache Dubbo has the communication mode of injvm, which can avoid the delay caused by the network and does not occupy the local port. It is a more convenient RPC communication mode for testing and local verification.Recently, I saw the code of containerd and found that it has similar requirements. Then I investigated whether gRPC has a similar ...

This note is the learning content of Alibaba cloud Tianchi Longzhu plan SQL training camp. The link is: https://tianchi.aliyun.com/specials/promotion/aicampsql preface This note is the learning content of Alibaba cloud Tianchi Longzhu plan SQL training camp. The link is: https://tianchi.aliyun.com/specials/promotion/aicampsql 1. Part ...

DAM Initialization Structure DMA: One request to transmit one data block, supporting the chain transfer function, can achieve one request to transmit more than one data block. A data block is a minimum of 1 data block and can be up to 1024 data blocks, each of which can be configured to be 8, 16, or 32 bits wide. /* DMA Initialize structure: ...

Recently, I was working on the project of connecting wechat applet to the Internet of things. However, the online data always did not match the demand. I finally succeeded in continuous experiments. I will make a brief record here. Effect display EMQX server configuration Replace the host address with the server domain name. If there is no IC ...

1 HelloWorld case 1) In the windows environment, create a new azkaban.project file. The editing content is as follows: Azkaban flow version: 2.0 Note: the function of this file is to parse the flow file using the new flow API method. 2.0 azkaban supports both properties configuration files and yml configuration files! 3.0 azkaban sup ...

UI implementation sharing: dynamic navigation bar text 1. Achieve results Let's take a look at the final effect Static graph Dynamic effect 2. Implementation details 2.1 html layout The element layout is relatively simple. It is divided into the central. toggle element and the list of surrounding li elements index.html &lt ...

1. Background overview Container mirroring is the first step in the transformation of container landing. Summarize several reasons for image optimization With the large-scale migration of application containerized deployments and accelerated version iteration, docker mirroring for optimizing infrastructure has the following main purposes Re ...