• Redis sentry — cache server


    Redis sentry Website: https://redis.io/ Note: the cache server can effectively improve the access efficiency of users 1. Precautions: A: The data structure of the cache should be K-V structure. As long as K is unique, the result must be the sameB: The total cached data cannot be stored all the time. It is necessary to […]

  • Mac shell script execution error operation not allowed


    On the Mac, you can download an SH script from a web page, QQ or wechat. Don’t be busy and hurry to execute it, or you will report the following errors sudo: unable to execute ./sh/ijiami-clang-install.sh: Operation not permitted What should we do when we encounter this problem? Don’t worry. Let’s analyze the reason, ls-l […]

  • PHP novice small problem summary


    We started learning PHP this week. I encountered many small problems when I first came into contact with it. How to solve these problems?PHP learning tutorial: https://www.kancloud.cn/yunzh…First: installation environmentBe sure to install this in order to work with the tutorialInstall the third and last.PS: some computers will have problems installing the third version, and the […]

  • Strange readonlysequence problem when using pipeline on serial port


    Learn from the previous pipelineOperation modeNow, the goal is to use pipeline for serial port read operation. With a little modification, the following code can be run directly. The protocol uses four consecutive 0xff as the end without header flag. The total length of data is 68 bits fixed length. I need to judge whether […]

  • Build cqui UI framework step by step


    In our work, we sometimes feel that some frameworks are very meaningful in terms of technical depth and breadth. However, if we sink down to look at the framework code and specialize in the code, we will be enlightened. We will learn a lot from it and slowly improve ourselves. In the end, we don’t […]

  • MySQL learning notes section 3 transaction isolation


    Transaction isolation Transaction isolation Characteristics of things: Acid Atomicity: atomicity Consistency: consistency Isolation: isolation Persistence: durability Advantages and disadvantages of isolation The higher the isolation, the lower the efficiency Isolation level of standard SQL Read uncommitted: when a transaction has not been committed, its changes can be seen by other transactions Read committed: after a […]

  • About solving the timeout problem of downloading NSIS wincodesign during packaging of electron builder


    These two dayselectron-builder; It’s really abused. I can only rely on Google to read the documentsLet’s move on to the topic Timeout problem • electron-builder version=22.9.1 os=10.0.19042 • description is missed in the package.json appPackageFile=G:\_personal\lasa-project-client\dist_electron\bundled\package.json • author is missed in the package.json appPackageFile=G:\_personal\lasa-project-client\dist_electron\bundled\package.json • writing effective config file=dist_electron\builder-effective-config.yaml • rebuilding native dependencies [email protected] platform=win32 arch=x64 […]

  • My 2020 review – Technology


    Looking at the “2019 summary” written in half of my notes, I always feel inexplicably happy. Then I want to say that time has really passed quickly. When I write the summary again every year, 2020 is the most magical year I have experienced in such a long time, including epidemic, financial crisis The world […]

  • Mybatis first level cache results in inconsistent query results with expected results


    Example SQL: @Transactional public RebateContract getInfo(RebateContract contract) { RebateContract rebContractInfo = rebateContractDao.getInfo(contract); logger.info(“agentId:” + rebContractInfo.getAgentId()); rebContractInfo.setAgentId(10000L); //Instead of querying, get the value of rebcontractinfo from the cache RebateContract rebContractInfo1 = rebateContractDao.getInfo(contract); logger.info(“agentId1:” + rebContractInfo1.getAgentId()); return rebContractInfo1; } Implementation results:Note: it must be in the same thingAfter one query in the same transaction, directly repair the […]

  • Learn go and rust mutex mutex through examples


    Mutex is used in concurrent programming. It means that a piece of data cannot be accessed by two processes at the same time Go // A Mutex is a mutual exclusion lock. // The zero value for a Mutex is an unlocked mutex. // // A Mutex must not be copied after first use. type […]

  • SQL: one of the most valuable skills


    In my career, I have learned a lot of skills, but no technical skills are more useful than SQL It is valuable in different jobs and disciplines Only need to learn once, do not need to learn again You look like a superhero. When you know that many people are not proficient in SQL, you […]

  • Rudely add something to your PHP SRC source code


    PS: This article is not to study PHP SRC source code, but to give you some results that seem useless or very useful *Do you usually encounter the following situations:1 then the outsourcing project is done well, but the other party won’t give money?XX does not pay wages, the project is done well3 when the […]