marcel/mermaid
1
0
Fork 0
mirror of https://github.com/mermaid-js/mermaid.git synced 2025-09-20 07:49:43 +02:00
Code Issues Packages Projects Releases Wiki Activity

Update entityRelationshipDiagram.md

Browse Source
This commit is contained in:
Neil Cuzon
2020-10-28 00:37:35 -07:00
committed by GitHub
parent 3f56830170
commit a9c3019433
1 changed files with 1 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

1
docs/entityRelationshipDiagram.md
View File

@@ -1,5 +1,6 @@
# Entity Relationship Diagrams # Entity Relationship Diagrams
**Edit this Page** [![N|Solid](img/GitHub-Mark-32px.png)](https://github.com/mermaid-js/mermaid/blob/develop/docs/entityRelationshipDiagram.md
> An entity–relationship model (or ER model) describes interrelated things of interest in a specific domain of knowledge. A basic ER model is composed of entity types (which classify the things of interest) and specifies relationships that can exist between entities (instances of those entity types). Wikipedia. > An entity–relationship model (or ER model) describes interrelated things of interest in a specific domain of knowledge. A basic ER model is composed of entity types (which classify the things of interest) and specifies relationships that can exist between entities (instances of those entity types). Wikipedia.
Note that practitioners of ER modelling almost always refer to *entity types* simply as *entities*. For example the CUSTOMER entity type would be referred to simply as the CUSTOMER entity. This is so common it would be inadvisable to do anything else, but technically an entity is an abstract *instance* of an entity type, and this is what an ER diagram shows - abstract instances, and the relationships between them. This is why entities are always named using singular nouns. Note that practitioners of ER modelling almost always refer to *entity types* simply as *entities*. For example the CUSTOMER entity type would be referred to simply as the CUSTOMER entity. This is so common it would be inadvisable to do anything else, but technically an entity is an abstract *instance* of an entity type, and this is what an ER diagram shows - abstract instances, and the relationships between them. This is why entities are always named using singular nouns.