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plantuml

How do I create relationship diagram using plantuml with lines touching the exact field

I have successfully created the ERD with standard notations as per the UML with reference to ERD Sample

But I want to make lines exactly touching the field names as specified in this question ERD Or UML

Diagram

is there and inbuilt facility available in plantuml or should I simply alter the x y position of the svg element using CSS ?

Solution

  • In theory it can be done using arrows from/to class members. However, it doesn't work as you'd expect:

    @startuml
' hide the spot
hide circle

' avoid problems with angled crows feet
skinparam linetype ortho

entity "Entity01" as e01 {
  * e1_id : number <<generated>>
  __
  * name : text
  description : text
}

entity "Entity02" as e02 {
  * e2_id : number <<generated>>
  __
  * e1_id : number <<FK>>
  other_details : text
}

entity "Entity03" as e03 {
  * e3_id : number <<generated>>
  __
  e1_id : number <<FK>>
  other_details : text
}

e01 ||.left.o{ e02::e1_id
e01 |o.right.o{ e03::e1_id
@enduml

    relations to class members

    I'd call it a bug in PlantUML, because the lines end in the center of the entity rather than its edge. You could possibly get it fixed by reporting it. However, I doubt you can get a result as nice as the diagram in your question.

    Playing around with up/down and left to right direction gets me a better result:

    @startuml
' hide the spot
hide circle

' avoid problems with angled crows feet
skinparam linetype ortho

left to right direction

entity "Entity01" as e01 {
  * e1_id : number <<generated>>
  __
  * name : text
  description : text
}

entity "Entity02" as e02 {
  * e2_id : number <<generated>>
  __
  * e1_id : number <<FK>>
  other_details : text
}

entity "Entity03" as e03 {
  * e3_id : number <<generated>>
  __
  e1_id : number <<FK>>
  other_details : text
}

e01::e1_id ||.up.o{ e02::e1_id
e01::e1_id |o.down.o{ e03::e1_id
@enduml

    But, again, I doubt this will work with your example. You can try!

    left to right direction hack

    Edit: Looking at this example, you can see that it's pretty close to the example you stated. I think the key is left to right direction.