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fix(docs): mmd detection

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Sidharth Vinod
2022-09-20 23:01:05 +05:30
parent ffdf268ba2
commit b9cb7e9898
12 changed files with 270 additions and 25 deletions
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8
docs/entityRelationshipDiagram.md
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@@ -114,7 +114,13 @@ Cardinality is a property that describes how many elements of another entity can
Relationships may be classified as either _identifying_ or _non-identifying_ and these are rendered with either solid or dashed lines respectively. This is relevant when one of the entities in question can not have independent existence without the other. For example a firm that insures people to drive cars might need to store data on `NAMED-DRIVER`s. In modelling this we might start out by observing that a `CAR` can be driven by many `PERSON` instances, and a `PERSON` can drive many `CAR`s - both entities can exist without the other, so this is a non-identifying relationship that we might specify in Mermaid as: `PERSON }|..|{ CAR : "driver"`. Note the two dots in the middle of the relationship that will result in a dashed line being drawn between the two entities. But when this many-to-many relationship is resolved into two one-to-many relationships, we observe that a `NAMED-DRIVER` cannot exist without both a `PERSON` and a `CAR` - the relationships become identifying and would be specified using hyphens, which translate to a solid line:
```mmd
```mermaid-example
erDiagram
CAR ||--o{ NAMED-DRIVER : allows
PERSON ||--o{ NAMED-DRIVER : is
```
```mermaid
erDiagram
CAR ||--o{ NAMED-DRIVER : allows
PERSON ||--o{ NAMED-DRIVER : is