@startuml

skinparam backgroundColor transparent
skinparam linetype ortho

skinparam node {
  backgroundColor transparent
  borderThickness 1
}

database "PostgreSQL" {
  node public {
    rectangle tables_public as "tables"
  }

  node extensions as "**extensions**" {
  }

  node API as "<size:20>api" {
    rectangle vf_api as "views + functions"
  }

  tables_public <-- vf_api
  extensions <-- vf_api
}

vf_api <-[thickness=3]-> () PostgREST

@enduml