I have an object type SPORTS ARENA that is supposed to lists all the sports held in that arena and an object type SPORT with all the infos about a sport:
SPORTS ARENA
name: string
sports: seq string
SPORT
name: string
disciplines: seq string
SPORTS ARENA <-->> SPORT (1:n) relationship, one sport can be held in only one arena (in this case it is like this)
and one arena can hold multiple sports.
This is an objects scheme and I want to convert it in a relational scheme with primary keys and foreign keys.
Usually in (1:n) relations you put in one table an attribute as foreign key refering the primary key of the other table.
In this case I have to deal with a sequence, so do I have to make an attribute that is a sequence of foreign keys? or how would the relational scheme look like?
-- Arena ARE exists.
--
arena {ARE}
PK {ARE}
-- Sport SPO is held in arena ARE.
--
sport {SPO, ARE}
PK {SPO}
FK {ARE} REFERENCES arena {ARE}
Note:
All attributes (columns) NOT NULL
PK = Primary Key
FK = Foreign Key