Basic concepts of database & lt; 1 & gt;

I. Terms

Data: Data

DataBase: DataBase, DB

DataBase Management System: DataBase Management System, DBMS

Ii. Data Model

1. Data Model Classification

The E-R Diagram for an instance is as follows:

Suppliers, projects, and parts are in many-to-many relationship: m: n: p

There is a many-to-many relationship between the warehouse and parts: m: n

There is a one-to-multiple relationship between warehouses and employees: 1: n

There is a leadership-led relationship between employees, with one-to-many connections: 1: n

2. Elements of the Data Model

Iii. Data System Mode