• Publish and subscribe to redis


    1、 What is it A message communication mode between processes: the sender (PUB) sends the message and the subscriber (sub) receives the message 2、 Command Subscribe C1 C2 C3 // you can subscribe to more than one at a time Publish C2 hello // publish to C2 Psubscribe new * // subscribe to multiple, wildcard* […]

  • Oracle (PLSQL) introduction 2


    Previous: introduction to Oracle I Learning video: https://www.bilibili.com/video/BV1tJ411r7EC?p=15 Arithmetic operator: + – */ Logical operators: and or not Comparison operators: ‘=’, ‘,’ < = ‘,’ > = ‘,’ < > ‘,’! = ‘. Note that “=” means equal rather than assignment, and the last two means not equal. Find column: select name,salary*15 from staff where […]

  • php-composer


    What is composer Use of composer, composer.json Please move to official documents for other documents install windows 1. Download and run composer- Setup.exe2. Manual installation php -r “readfile(‘https://getcomposer.org/installer’);” | php New file composer.batecho @php “%~dp0composer.phar” %*>composer.bat linux curl -sS https://getcomposer.org/installer | php mv composer.phar /usr/local/bin/composer Modify source Configure alicloud source composer config -g repo.packagist composer […]

  • Detailed explanation of cron expression in timed tasks


    1. Preface We often usecronExpression to define the execution strategy of timed tasks. Today we will summarizecronSome knowledge of expressions. 2. Definition of cron expression cronAn expression is a string that is composed of6Spaces are divided into7Each domain represents a time meaning. The format is as follows: [Second] [minute] [hour] [day] [month] [week] [year] Generally, […]

  • CSS weight


    1. What is CSS weight? Css6 basic selector CSS weight refers to the priority of css6 basic selectors. The CSS style with high priority will override the CSS style at the bottom of the priority. The higher the priority, the higher the weight, and vice versa. Css6 basic selector: a) , ID selector ({}) b) […]

  • Translation of atom Flight Manual: 4.2 key map


    Drill down key map Key table files are JSON or cson encoded files that contain nested hash tables. They work like style sheets, but they specify the role of shortcuts that match the elements of the selector, rather than applying style attributes. Here are some examples of shortcut keysatom-text-editorEffective when pressed on element: ‘atom-text-editor’: ‘cmd-delete’: […]

  • Cross domain failover of nginx configuration


    Nginx configuration does not work across domains, as follows server { listen 80; server_name localhost; #Interface forwarding location /api/ { #Allow request address cross domain * as wildcard add_header ‘Access-Control-Allow-Origin’ ‘*’; #Set request method cross domain add_header ‘Access-Control-Allow-Methods’ ‘GET, POST, OPTIONS, PUT, DELETE’; #Set whether cookie transfer is allowed add_header ‘Access-Control-Allow-Credentials’ ‘true’; #Set request header […]

  • An introduction to the messaging model of [golang] NATs


    Catalog The messaging model of NATs What is NATS Subject based messaging Publish subscribe Request reply Queue group Acknowledgements The messaging model of NATs @ What is NATS NATs is an open source, lightweight and high performance native message system developed by go language. NATs messages are handled by the subject and do not depend […]

  • PlayJava Day026


    1. Generic: refers to any object type public class CC {} C c = new C(1) ; 2. Restrict generics: for inheritance public class Demo {} Demo demo = new Demo(new Son()) ; //Here, son can be sonclass or fatherclass, not other classes Son son = demo.getObject() ; 3. Wildcard generics: Demo> demo ; demo.func() […]

  • Sublime text regular must pay attention to! Tenth wildcard substitution variable


    Well, I’ll admit that I have a title file to express my sunshine mood after depression. We usually use wildcards when dealing with CSV As follows: (.*?)\t(.*?)\t(.*?)\t(.*?)\t(.*?)\t(.*?)\t(.*?)\t(.*?)\t(.*?)\t(.*?)\t(.*?)\n When we need to replace (convert) to the format or SQL we need, there will be an inexplicable problem. 1and10It’s the same. That’s 10 for 1. So how […]

  • Essentials of java knowledge (2)


    I. set 1. Iterable v.s. IteratorBoth are interfaces, and the inherited interface in collection is Iterable.Iteratable expresses that the collection has the ability of iterative access, while iterator represents the implementation, which can be from small to large or from large to small. https://zhuanlan.zhihu.com/p/52366312 2. Comparable v.s. Comparator https://www.cnblogs.com/skywang12345/p/3324788.html 3. set https://www.cnblogs.com/LittleHann/p/3690187.html Collection needs multi-purpose […]

  • Cross domain problem handling between yii2 and Vue


    Add the following to the controller header(“Access-Control-Allow-Origin: *”); //If you need to set up a cross domain request that allows all domain names to initiate, you can use the wildcard * to write your own domain name if you restrict your domain name. //The response type * represents a wildcard, which can indicate fixed types […]