• Java basic grammar emesis finishing


    preface My theoretical knowledge of Java has not been very good, so I decided to start from 0 and sum up what I thought and what I didn’t know before. Come on!! insist!!! Java overview Three systems of Java 1. Javase Standard Edition 2, JavaEE Enterprise Edition (mainstream) 3, javame Mini Edition JDK download and […]

  • How to calculate the item category in the one order line item


    There is a field called item category in the line item of one order. After we add a product to the line item, the item category will be brought out automatically. How is this value calculated? Check CRMD_ ORDERADM_ 1. Can find background object_ The value stored in the type field is bus2000130 Configuration of […]

  • Pyspider all will encounter many obstacles! (Python3.7)


    Case 1: ValueError: Invalid configuration: – Deprecated option ‘domaincontroller’: use ‘http_authenticator After installing pyspider successfully, the above problems will occur after running pyspider all; terms of settlement: In the installation package of pyspider, find the webui folder, and then find the webdav.py File, find the following code:’domaincontroller’: NeedAuthController(app), It is amended as follows: ‘http_authenticator’:{ ‘HTTPAuthenticator’:NeedAuthController(app), […]

  • [flutter 1-7] dart language — variable


    Author: VladSource Vlad (official account: fulade_ Me) At the goto Conference on October 10, 2011, two Google engineers released “dart”, a new programming language designed to help developers build web applications. Dart 1.0 was released on November 14, 2013. Dart language is used in our daily development of flutter, so it is necessary for us […]

  • Using laravel to deal with ten million level data easily


    stayLaravelUsed incursorTo query and process data (easily handle tens of millions of data) Scene of the incident Recently, I encountered the problem of insufficient memory in the project. The PHP memory in the test environment is only 64M. When exporting, there is a large amount of data. At this time, there will be a memory […]

  • Nonlocal keyword


    1. What is the role of nonlocal? What are the features of Python? In the outer function, you can use the keyword of the inner function directly. In Python, the definition of a function can be nested, that is, the body of a function can contain the definition of another function. 2、Demo Cases without non […]

  • support AngularJS Mult & Single Auto-Complete


    Requirement Based on angularjs UI bootstrap, users can select multiple or single. Other prerequisite details: Enter at least three duplicate removal Support user keyboard enter, enter and select When the user loses focus on the input box Handle the operation of user Ctrl + C / V Extension:There is a phenomenon in most auto complete, […]

  • Learning SQL Server (2): data table constraints


    –Data table constraint: by making some rules, the data stored in the database is standardized, correct and complete. –Non NULL constraint the field cannot be empty keyword: not null –The value of the unique constraint field cannot be repeated in this table and can be null, but only once. Keyword unique –The default constraint gives […]

  • Deep understanding of MySQL index


    preface When referring to MySQL database, we will think of several keywords in our mind: index, transaction, database lock, etc. index is the soul of MySQL, a sharp tool for query and the top priority in interview. You may know that the bottom layer of the index is a B + tree, which will speed […]

  • Learning SQL Server (4): multiple query statements


    –======================Inquiry=========================–Select * from table name –Simple query — query the specified column select the specified column from table nameselect id,name,sex,age from Employee–Note: select age * 14 from employee –Simple query — query the first few lines of information, select top rows * from table nameselect top 5 * from Employee –Query the name, gender and […]

  • Select and jump statements


    1. Case statement The case statement uses a simple structure to select values, and more importantly, it can also be used to set the value of a variable –Case syntax format: case input_name When expression then result execution …… end; Description: first set the value of a variable, and then compare the values given after […]

  • Mantle uses


    Mantle can easily write a model layer code. It is easy to deserialize JSON or serialize it to JSONMTLModelImplementation in subclass<MTLJSONSerializing>Agreement) Using an interpreterMTLJSONAdapterModel to transform objects. NSError *error = nil; MyObject *myObject = [MTLJSONAdapter mod elOfClass:MyObject.class fromJSONDictionary : jsondictionary error: & error]; // convert JSON dictionary to model object NSDictionary *JSONDictionary = [MTLJSONAdapter JSONDictionary […]