Entity-relationship diagrams (ERD) are essential to modeling anything from simple to complex databases, but the shapes and notations used can be very confusing. This guide will help you …

2023年12月21日 · An Entity Relationship Diagram (ERD) is a type of diagram that lets you see how different entities (e.g. people, customers, or other objects) relate to each other in an …

2021年8月1日 · Overview of different types of keys used in E-R diagrams. How to establish a primary key from a set of alternatives. Composite, superkey, candidate, primary and alternate …

2025年3月11日 · An Entity Relationship Diagram (ERD) is a graphical representation that shows how entities, such as people, objects, or concepts, relate to each other within a system. ERDs …

实体关系图也被称为 ERD、ER 图、实体联系模型、实体联系模式图或 ER 模型，是一种用于数据库设计的结构图。 一幅 ERD 包含不同的符号和连接符，用于显示两个重要的資訊： 系统范 …

ER diagrams can be used for various purposes, ranging from abstract logical models devoid of any implementation details, through to physical models of relational database tables. It can be …

ERD stands for entity relationship diagram. People also call these types of diagrams ER diagrams and Entity Relationship Models. An ERD visualizes the relationships between entities like …

An entity-relationship diagram, or ER diagram, models the logical relationships between entities and thereby can help engineers troubleshoot issues or discover inefficiencies in existing …

本文介绍了实体关系模型（ER Diagram）中超级键（Superkey）、键（Key）、候选键（Candidate Key）和复合键（Composite Key）的概念，并通过学生选课实例展示了如何建 …

Physical ERD symbols. The symbols below are used at the most granular level of ERDs—physical data models. Some elements are also used for logical data models. Tables …