Database relations




Basic database relations:




One to one relation definition:

Relation one to one exist when one value from database entitiy (table) can be assigned only to one value from other entitiy  in this database. See example here.




One to many relation definition:

Relation one to many exist when one value from the example database entitiy (table) can be assigned to many values from the other entitiy (table) in this database. See example here.

Many to many relation definition:

Relation many to many exist when one value from first database entitiy (table) can be assigned to many values from second entitiy (table) in this databse and one value from second entitiy can be assigned to many values from first entitiy. See example here.

Copyright © 2015-2016 • All Rights Reserved • database-definition.com

Leave a Reply

19 − two =