ERD, 即 entity Relationship diagram, 实体关系图。使用一组定义的符号,如矩形、菱形、椭圆和连接线来描述实体、关系及其属性的相互联系。 ER图的组成部分 ER 图由实体、关系和属性组成。 并且不同的记法有不同的符号。 这里介绍比较常用的两种技法:Chen notation style和Crow's Foot style Chen notation style P...
通过从应用程序工具栏中选择“ 项目”>“新建”来创建新项目 在New Project窗口中,输入Bus Route Management作为项目名称,然后单击Create Blank Project。 要创建ERD,请从工具栏中选择图表>新建。在New Diagram窗口中,选择Entity Relationship Diagram,然后单击Next。输入巴士路线管理作为图表名称,然后单击确定。 我们首先...
> Entity Relationship Diagram (ERD) Posted by Allison Lynch | Part 1: What Is An Entity Relationship Diagram? Part 2: History Of Entity Relationship Diagrams Part 3: Usage of an ER Diagram Part 4: Benefits of Entity Relationship Diagram Part 5: Symbols and Notations of Entity ...
实体关系图(Entity-Relationship Diagram, ERD) 实体关系图包括:数据对象、描述数据对象的属性以及数据对象之间的关系。 www.slideshare.net|基于10个网页 2. 实体关联图 「实体关联图」(Entity-relationship Diagram, ERD)是使用图形表示资料库的结构,主要的目的是显示资料库各资料表间的关 … ...
Because I didn't know the relevant knowledge in detail, there was an error when drawing the ER diagram this week. Here is an introduction to the ER diagram. What is ERD? ERD, namely entity Relationship diagram, entity relationship diagram. Use a defined set of symbols such as rectangles, ...
此種模型主要是以資料為主要考量方向的『實體關聯圖』(EntityRelationshipDiagram，簡稱ERD)，大部份是使用在資料庫的設計使用 第三種是以『物件導向』為主的模型(ObjectOriented)此模型的代表則為『統一塑模語言』(UnifiedModelingLanguage，簡稱UML)這三種模型所要代表和展現出來的意義皆有所不同，也就是所要描述的構...
What is an Entity Relationship Diagram (ERD)? 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 people, things, or concepts in a database. An ERD will also of...
通常所说的 E-R 图(外文全称 Entity Relationship Diagram,简称 ERD)长这个样子: 而有时候它也可以是这个样子↓ 确切的说它是用统一建模语言(UML)中的类图所表示的 E-R 图。 总之,上面的两种图都是 E-R 图,只是表现形式、符号、包含的信息量(精确程度?)不太一样。
First of all, what is an Entity Relationship Diagram? Entity Relationship Diagram, also known as ERD, ER Diagram or ER model, is a type of structural diagram for use in database design. An ERD contains different symbols and connectors that visualize two important information:The major entities...
What is an Entity Relationship Diagram (ERD)—and how to use it Table of contents Experienced designers know real-world relationships can be tricky to capture in simple flowcharts. But unlike humans, computers can apply clear, consistent logic to relationships by following an entity relationship d...