Tag:Data Volume

  • MySQL large data paging optimization


    Reference article: Paging query method and its optimization for millions of data in MySQL MySQL paging query optimization     The key points are as follows: In the process of optimizing paging statements, you must pay attention to adding sorting fields to the query statements, and you must create your own tables. Some of them […]

  • How to extract value from messy medical big data (1)


    Business Tags: hospital information integration platform, Internet hospital, Internet nursing, chronic disease follow-up Technical labels: ESB, ETL + CDC, NLP, FAAS, SaaS, Hadoop, microservice   Technology wechat group:Add wechat: wonter send: technical QMedical wechat group:Add wechat: wonter send: Medical Q   —————— BEGIN —————— How to extract value from messy medical big data (1) How […]

  • Spark performance tuning shuffle tuning and troubleshooting


    Shuffle tuning of Spark Tuning This section begins with an explanationShuffle core concepts; And then forHashShuffle、SortShuffleCarry out the optimization; Next, yesMap side、Reduce sideOptimization; And then for theData skewProblem analysis and optimization; Finally, the process of spark runningTroubleshooting。 This article starts with the official account.Learn big data in five minutes】, our company focuses on big data […]

  • App startup page optimization


    There are many app startup pages that are still the same splash activity, and then jump to mainactivity. First, splash loads the data once, and then it loads the data after entering main, so you have to wait for two loads. What if the reverse is true Here, mainactivity can be loaded first, and then […]

  • MySQL optimization 5 (efficiency of association query, sub query and in)


    Now let’s talk about the efficiency of association query and subquery( We have to cooperate with specific scenarios. It’s really not good to analyze them in detail. Write out two solutions, and choose which one has shorter execution time.) 1. For MySQL, it is not recommended to use subquery and join because the efficiency of […]

  • Continuous definition of SaaS mode cloud data warehouse + bi


    Overview of cloud data warehouse Today, I’d like to discuss with you what new things can be found in our SaaS cloud data warehouse plus Bi. Let’s take a look at some overview of cloud data warehouse. It is predicted that by 2025, global data will grow to 175zb, and China’s data will grow to […]

  • PHP + MySQL 10 million level data processing case (2) significance of sub table


    A series of articles: PHP + MySQL 10 million level data processing case (2) significance of sub table PHP + MySQL 10 million level data processing case (1) (sub table) Previous blogPHP + MySQL 10 million level data processing case (1) (sub table)We have talked about the meaning of sub table and one of its […]

  • PHP common class library tool component 2


    symfony/http-foundation github https://github.com/symfony/http-foundation reference resources https://symfony.com/doc/curre… nesbot/carbon github https://github.com/briannesbitt/Carbon An API extension for datetime that supports 281 different languages predis/predis github https://github.com/predis/predis PHP redis client supports the operation of redis list, set, hash and other data structures. Phpredis extension is recommended for high performance scenarios https://github.com/phpredis/p… guzzlehttp/guzzle github https://github.com/guzzle/guzzle PHP HTTP client. Supports synchronous and […]

  • Interview series 1: select 10 big data interview questions (mixed type) – with detailed analysis of answers


    The official account (five minutes big data) will launch a series of big data interview articles.Five minute interview, this series willIn depth study of the real interview questions of major manufacturersAccording to the written questionsExpand relevant knowledge pointsTo help everyone successfully enter the big factory! Big data pen interview series articles are divided into two […]

  • Application of process pool in project without regret


    preface: Recently, after looking at the content of thread pool and learning its internal principles in combination with the source code, I thought, have you ever actually used thread pool in a project? If you think about it, thread pools are used in many parts of the project. Let’s talk about the recent application of […]

  • The implementation principle of Python dictionary


    The implementation principle of Python dictionary Pseudo code a = {} a[‘key1’] = 1 a[‘key2’] = 6 del a [‘key1’] Underlying implementation Python interpreter executes a = {}Python interpreter read here, for example, will give five consecutive memory space, there are five consecutive memory addresses, can put data The Python interpreter executes a [‘key1 ‘] […]

  • What is the N + 1 problem and how to solve it


    N+1It is a problem in reading the related data of ORM (object relation mapping). What do you meanN+1First, think about a question: Suppose there is a user table and a balance table, which are passed through theuser_idMake a connection. Now there is a needQuery users older than 18 and their respective balances。 This problem is […]