• Mybatis select record encapsulation


    Select record encapsulation Returns a list collection. Resulttype writes the type of the elements in the collection <!– public List<Employee> getEmpsByLastNameLike(String lastName); –> <!– Resulttype: if a collection is returned, write the type of the elements in the collection — > <select id=”getEmpsByLastNameLike” resultType=”com.atguigu.mybatis.bean.Employee”> select * from tbl_employee where last_name like #{lastName} </select> Returns the […]

  • Summary of MySQL


    Basics 1. What are SQL, DB and DBMS and their relationship? DB: Database (a database that actually exists as a file on the hard disk)DBMS: Database management system (database management system, common are: MySQL, Oracle, DB2, Sybase, sqlserver…)SQL: Structured query language is a standard general language. Standard SQL statements are suitable for all databases DBMS […]

  • ABP plus DDD development: low coupling, reusable and extensible work order business module – Introduction and integration


    preface Many scenarios [monomer + modularization] are more suitable than microservices, with low development difficulty, strong code reusability and scalability. There are some difficulties in modular development, such as module startup and unloading, dependence and communication between modules. asp.net core  abpIt provides us with the ability of modular development and other basic functions. be based […]

  • Basic summary of orcla (2)


    Set operator Notes on using set operator Column names and expressions in the select list should correspond to * * quantity and data type * * Parentheses can change the order of execution Order by clause: Can only appear at the end of a statement You can use the column name, alias, or relative position […]

  • Using spring + springboot + mybatis technology to realize the operation of adding, deleting, modifying and checking of enterprise employees


    Business description Requirement description Any enterprise will involve the addition, deletion, modification and query of employees. In the current business system design, we need to design and implement the management of employee information. Business framework analysis In staff information management, it is necessary to add, modify, query and delete employee information, as shown in the […]

  • Simple instance statement of SQL stored procedure


    1 create database bookshop 2 go 3 4 use bookshop 5 go 6 7 / * personnel list*/ 8 CREATE TABLE employee( 9 emp_no char(5)not null primary key, 10 emp_name char(10) not null, 11 sex char(2) not null, 12 dept char(4) not null, 13 title char(6) not null, 14 date_hired datetime not null, 15 birthday […]

  • Python packet processing


    In daily data analysis, we often encounter tasks that need to be grouped by column, such as calculating the number of people in each department of a company, calculating the average wages of men and women in each department, calculating the average wages of employees in different years, and so on. In this kind of […]

  • Pandas data analysis — detailed explanation of super easy to use groupby


    WeChat official account: “Python reads money”If there are any questions or suggestions, please official account message. In the daily data analysis, it is often necessary to analyze the dataDivide into different groups according to one (more) fieldFor example, in the field of e-commerce, the total sales of the whole country are divided by provinces, and […]

  • How does CRM help enterprises bring benefits?


    In the traditional customer information management, the management of customer information by employees is very messy. Customer information is usually scattered in the hands of an employee, so it is difficult to manage together. So the customer information between enterprise departments is difficult to be connected systematically, for enterprises, customer information management will cause great […]

  • Review of MySQL 1: Basics


        Weekend time is short, but also relaxed and happy, in this hot summer sitting on a small bench, blowing air conditioning and drinking tea, I take you to gently open my article link, leading you to review the content of MySQL in front of the screen, I hope you can gain something. This […]

  • Why do enterprises need a set of purchasing management system?


    For manufacturing and other types of enterprises, such as wholesale, warehousing, retail, computers and accessories, the types of equipment need to be managed are more complex. In the traditional management mode, most of the data collection of goods and equipment procurement is done by special staff. The purchaser is either in the procurement or on […]

  • Writing SQL cases based on MySQL (1)


    Database SQL file in the database: https://blog.csdn.net/GongmissYan/article/details/102937816 #Basic query /* Syntax: Select query list From table name; Query lists can be fields in tables, constant values, expressions, and functions The query table is a virtual table */ #Query single field select last_name from employees #Query multiple fields select last_name ,salary,email from employees #All fields in […]