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| -rw-r--r-- | assignments/1/README.md | 25 |
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diff --git a/assignments/1/README.md b/assignments/1/README.md index c3b284d..f2e1989 100644 --- a/assignments/1/README.md +++ b/assignments/1/README.md @@ -44,6 +44,31 @@ An `entity instance` is a specific occurrence of the `entity type`. .i.e. a spec Give a simple example of an E-R diagram for each of the following concepts: a. Associative entity + > An entity type that associates the instances of one or more entity types and contains attributes that are peculiar to the relationship between those entity instances. + + Project ||-<- Policy ->-|| SoftwareLicense + ```plantuml + @startuml + entity 'Project' as project { + *id: number + *name: varchar(255) + } + entity 'Policy' as policy { + *id: number + *classification: number + *project_id: number + *software_license_id: number + } + entity 'SoftwareLicense' as license { + *id: number + *spdx_id: varchar(255) + *name: varchar(255) + } + project ||..|{ policy + license ||..|{ policy + @enduml + ``` + b. Weak entity c. Unary relationship |