Tag:Zhang San

  • Map


    1. Map Map is an unordered key-value based data structure. Map in GO language is a reference type and must be initialized with Make before it can be used. 1.1.1 map definition The definition syntax of map in GO language is as follows map[KeyType]ValueType in, KeyType: Indicates the type of key. ValueType: Indicates the type […]

  • About the interception of the result set by mybatis interceptor


    Just learningMybatisI found a lot about interceptors on the InternetMybatisI have tried to write several articles on interceptors, but I have never found a suitable one for intercepting result sets (ps: don’t spray me, after all, I’m a novice). I also asked questions on segmentfault, but I still didn’t find one easy to understand. Later, […]

  • In laravel {} and {!!!} Differences between


    1. {}} and {!!!} The {}} supports escaping a piece of HTML code, which is only output as a normal string, {!!!!} Transfer is not supported. A piece of HTML code can be parsed normally1.2 what does it mean specifically? Let’s demonstrate the code2. RoutingRoute::get(‘demo’,’[email protected]’); 3. Controller[url=][/url] <? phpnamespace App\Http\Controllers; use Illuminate\Http\Request; Class democontroller extensions […]

  • Redis – article voting


    Refer to “redis practice” demand 1. The article information includes: title, content, link, publishing time, publisher, and vote for yourself after publishing.2. One person can only vote for one article.3. Articles can only be voted for seven days.4. The article voting ranking takes into account the release time and the number of votes, and takes […]

  • thinkphp5 latavel7.* Using redis configuration


    preface 1. Nowadays, many scenarios of PHP development business need to use redis to reduce the pressure on the database. For example, ranking in seckill / live broadcast, etc2. Make sure you install and enable redis expansion before using 1. Thinkphp5 connect to redis $redis = new Redis(); $redis->set (“name”, Zhang San); $value = $redis->get(“name”); […]

  • Elasticsearch uses series – basic queries and aggregate queries +sql plug-ins


    Elasticsearch uses series es introduction and environment construction Elasticsearch use series -es basic operations of adding, deleting, checking and modifying +ik word segmentation Elasticsearch uses series – basic queries and aggregate queries +sql plug-ins Elasticsearch uses series – Net6 docking elasticsearch Elasticsearch uses series docker to build elasticsearch clusters 1、 Basic query 1.and query must […]

  • Java stream technology


    Stream technology Common intermediate operation methods for stream streams (stream can still continue to perform other operations after this method is executed) Stream filter Filter the data in the stream Stream limit intercepts the number of specified parameters Stream skip skips the data of the specified number of parameters and returns the stream composed of […]

  • Tips for using list to map (collectors.tomap) in java8


    In actual projects, we often use the list to map operation. In the past, we might use the for loop traversal method. for instance: Define the class first: /Simple object Then there is a list: List<User> userList = Lists. newArrayList( The format we want to convert to map is: A-> Zhang San Past practice (cycle): […]

  • Mvcc principle and unreal reading of [MySQL] transactions


    First of all, we should understand mvcc. Mvcc is called multi version concurrency control, which is actuallySave a snapshot of the data at a certain time node。 We actually hide two columns per row,Create version number, expired (deleted) version number, every time you start a new transaction,The version number will be incremented automatically。   Take […]

  • Vue3 family bucket upgrade Guide – composition API


    1、setup() The most important composition API in vue3 is the setup method, which is equivalent to the entry of components. All composition APIs must be used in setup (). Setup is executed before the component instance is initialized (before beforecreated). It is the entry function of the whole component. At this time, the data and […]

  • Implementation of Vue elementui exporting excel form


    Implementation of Vue elementui exporting excel form In daily business, we often encounter excel export function. How to use it The import and export of Excel depend onjs-xlsxTo achieve. stayjs-xlsxOn the basis ofExport2Excel.jsTo facilitate the export of data. Dependencies and on-demand loading required for installing Excel becauseExport2ExcelNot only dependentjs-xlsxAlso dependentfile-saverandscript-loader。 So you need to install […]

  • Vue3 family bucket upgrade guide II differences between ref, toref and torefs


    Ref is a copy of the original data. When the ref data is modified, the view in the template will change, but the original data will not change.Toref is a reference to the original data. When you modify the toref data, the original data will also change, but the view will not be updated. Ref […]