physical.erd

entity Person
  id id type autoincrement
  attribute name type text
  attribute alive type boolean
  
relation Father
  one optional Person // For now, this order is important, the one with 'one' should be the first for unary relations
  multiple optional Person

relation Mother
  one optional Person
  multiple optional Person

relation Friends(Is friends with)
  multiple optional Person
  multiple optional Person

entity Car
  id id type uuid
  attribute brand type enum(volvo, BMW, ferrari, volkswagen)
  attribute color type varchar(20)
  attribute price type float
  attribute dec_price type decimal(10, 2)
  attribute image type blob

relation Ownership(Is owner)
  multiple optional Person
  multiple optional Car
  attribute since type datetime

table person from entity Person
foreign key father for Father
foreign key mother for Mother

table car from entity Car

table ownership from relation Ownership

table friendship from relation Friends

// integer, float, boolean, varchar(len), date, time, datetime