Programmer Help

ajax crawling Sometimes when we use Requests to grab the page, the result may be different from what we see in the browser. We can see the normal page data in the browser, but we don't get the result using Requests. The reason is that Requests gets the original HTML document, while the page in the browser is the page passing by again The result ...

1, MHA introduction At present, MHA (Master High Availability) is a relatively mature solution in the aspect of MySQL high availability. It is developed by yoshimaton (now working for Facebook), a Japanese DeNA company. It is an excellent high availability software for failover and master-slave improvement in MySQL high availability environm ...

1, Encapsulate database operations: store all database operations in the dao package. (1) using single column pattern to design a tool class for database Connection and provide a Connection object. package dao; import com.mysql.jdbc.jdbc2.optional.MysqlDataSource; import javax.sql.DataSource; impo ...

One to one relationship There are two ways to implement one-to-one association in Hibernate 5: primary key Association and foreign key Association. 1. Primary key Association Key point of primary key Association: two associated tables share a primary key value. For example, if a company is registered ...

Special operation flow in IO flow Summary: The special operation flow in IO flow, as the name implies, has its special function; Standard I / O stream Summary: Standard I / O streams are used for keyboard input and printout; that is, the Scanner class and System.out.println(), which we usually u ...

This article is based on "Effective Python - 59 effective ways to write high-quality Python code" [U.S.] Brett Slatkin translated the contents of this book, wrote his own insights in some aspects, and excerpted some as reading notes for future encouragement. Invasion and deletion. Article 31 ...

1, Functional analysis of implementation (1) The function of adding the verification code on the landing page plays a certain security role. The login can be realized only when the correct verification code, user name and password are entered. (2) Realize the function of querying database. In the page ...

1, Understand MongoDB database? Introduction: MongoDB is written by C + + language. It is an open source database system based on distributed file storage. It is a document oriented database. It is JSON like data format, free and flexible. Advantages: scalable clustering, mass data storage, fast q ...

Catalog 1, Architecture introduction 1. What is Flask? 2, Flask form operation 3, What is flask Sqlalchemy? 1. How to configure the database? 2. Define model 3. Model column type 4. Model column properties 5. Data query 6. Paging implementation 7. Flask migrate database migration 1. Model ...

concept Inversion of Control (IoC) is a design principle in object-oriented programming, which can be used to reduce the coupling between computer codes. It is a programming idea, which can let us design better programs. Dependency injection (DI) is a way to realize IOC. By this way, we can transf ...