• Modify user information changeinfo


    When judging the persistence layer: Problem: there is such a problem when modifying user information. For example: the user’s email is not required. It was not empty originally. At this time, the user deletes the mailbox information and submits it. At this time, if it is not empty to judge whether it needs to be […]

  • Senior architects talk about the rise of DDD, solving problems and implementation steps


    Foreword- Why can DDD catch fire? Let’s not discuss the definition of DDD, but sort out the background of the popularity of DDD. According to the routine I learned, it is always why first, then what problems to solve, what things to use, and finally how to use. We all know that in recent years, […]

  • These 15 PHP interview questions can be done, and you can basically find a job


    Series articles: PHP classic interview questions, there are answers These 15 PHP interview questions can be done, and you can basically find a job 2021 this PHP interview question is well summarized and worth learning 1、FILEWhat do you mean? (5 points)The full path and file name of the file. If used in an include file, […]

  • Can you really use the index database?


    The drawing is from freepik Reprinted from:Can you really use the index database? It’s also easy to use indexes. However, it’s one thing to be able to use indexes, and it’s another thing to have a deep understanding of the principles of indexes and be able to use indexes properly. 1、 Foreword Whether in an […]

  • Do you know how database indexing works?


    Transferred from technology / translation boss – Mr. Li SONGFENGOriginal address:https://www.ituring.com.cn/article/986 Translator’s press: I accidentally searched this article (Q & A) in stackoverflow during translation today. I feel it necessary to translate it. Not only because the article itself is wonderful, but more importantly, it shows an important rule of writing articles (especially technical articles) […]

  • Tencent cloud logstash actual combat 2- synchronize the data in MySQL to elasticsearch


    Logstash can also be used to synchronize data in relational databases such as MySQL and PostgreSQL to other storage media. The following describes how to use itTencent cloud logstashSynchronize data into the MySQL product. Create pipe On the “pipeline management” page, click the “new pipeline” button to create a pipeline: Enter the pipeline configuration page, […]

  • (4) MySQL advanced SQL optimization (optimization of common SQL)


    1. General Earlier, we introduced how to optimize queries through indexes in MySQL. In daily development, in addition to using query, we will also use some other common SQL, such as insert, group by, etc. How should we optimize these SQL statements? This section will introduce some optimization methods for these SQL statements. 2. Optimize […]

  • Webshell safety dog (3)


    1. Use the method contained in the file to bypass WAF: Here is a PHP code: Principle: apply$_ The parameter obtained by get() is assigned to the $filename variable, and then include contains the variable. If you directly access this PHP code, you will be intercepted by WAF   At this time, use PHP online […]

  • Convert BigDecimal type to string type during JSON serialization


    The BigDecimal data returned from the back end to the front end may lose precision in some cases. In order to avoid this situation, we generally convert BigDecimal into string to avoid it. 1、 Simple mode @JsonFormat(shape = JsonFormat.Shape.STRING) private BigDecimal rate 2、 Complex mode //Customize the serialization method first This work adoptsCC agreement, reprint […]

  • Flink + hologres 100 million users real-time UV accurate weight removal best practice


    Introduction:Flink + hologres 100 million users real-time UV accurate weight removal best practice UV and PV computing are usually divided into two scenarios because of different business requirements: Offline calculation scenario: T + 1 is used to calculate historical data Real time calculation scenario: real-time calculation of daily new data and de duplication of user […]

  • 【GO】gorm


    reference material[1] Connect to database[2] Official documents 1. Introduction gormIs usedormMapping, so you need to define the name of the table to operate onmodel, you need to define one in gostruct, structThe name of is the name of the corresponding table in the database. Note:gormlookupstructWhen the name corresponds to the table name in the database, […]

  • What is the smart field of SAP ui5


    Smartfield controls interpret metadata representing entity relationship models, data types, service functions, and annotations in OData services for automatic generationUnderlying internal controlsAnd reduce the amount of code required to develop applications. In some cases, OData entities derive from the binding context of the control. The properties of the OData entity changed or displayed with the […]