Programming VIP

1. Bitwise operator Bitwise operators are operators that evaluate on binary numbers. The bit operator first converts the operand into a binary number, then performs a bit operation, and finally changes the calculation result from binary to decimal. MySQL supports the following bitwise operators: 1.1 bitwise and operators The bitwise ...

DCL & Function & Index review Multi table relation: One to many: Add multiple foreign key columns to a general table,The value is the primary key of a table To ensure the validity and integrity of data,Generally, after the table is under construction,Adding foreign key constraints by modifying table relationships alter table M ...

Original author: https://zhuanlan.zhihu.com/p/364044293   From 0 to server development -- TinyWebServer preface: Project code for modification, complete annotation and addition of functions: https://github.com/white0dew/WebServer What is it—— C + + lightweight Web server under Linux helps beginners quickly practice network pr ...

Core content of MySQL execution plan As we all know, mysql performs query optimization when executing queries. To put it simply, when executing, first generate an execution plan based on cost and rule optimization, and then execute the query according to the execution plan. This article mainly introduces the meaning of each output item of EXPL ...

Source code acquisition: download from "resources" on the blog home page! 1, Project brief Function: the project is a hospital management system written with springboot+layui+shiro. The business of the system is relatively complex. There are 36 tables in the database. The project is divided into outpatient management, inpatient m ...

background Beginner Java, read green hand The tutorial of connecting Java to Mysql is missing the process of configuring jar files. Only Windows environment and Linux environment can be downloaded For novices, I'm very confused, so record it If you have the same environment as me, I hope you can help Use environment Computer: Macbook A ...

1, Prepare test environment 1.1. Create data table /* Employee table */ CREATE TABLE `emp` ( `id` int(8) NOT NULL AUTO_INCREMENT, `name` varchar(20) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL DEFAULT '', `job` varchar(9) NOT NULL DEFAULT '', `hiredate` date NOT NULL, /* Entry date */ `sal_grade` int(8) NOT NULL, `age` ...

Introduction: this chapter mainly explains the related technologies of dynamic web page crawling. The crawling of dynamic web pages mainly includes reverse analysis method and simulation method. Today, we will mainly introduce the reverse analysis method. Later, we will focus on the use of selenium Library in the simulation method. Dynamic ...

SSM framework integration ideas (personal view) The ssm framework is frequently used in projects. In order to focus on the business code in the project, I sorted out the steps to be used by the ssm framework. The following figure is the result of the sorting. (the green box in the figure is the key point of the process, and the changes in each ...

catalogue After the execution of SQL statements in MyBatis, the processing of results     1. resultType result type refers to the java object that the data is converted to after the sql statement is executed. The java type is arbitrary     2. Alias the resultType of the returned result     3. Save q ...