Apologies in advance if this is a silly question. I recently faced this question while revising for databases, so I wish to check if my understanding is correct.
I understand that participation constraint is referring to the number of instances of an entity that can participate in a relationship. (E.g. Total and Partial).
Referential integrity is also a constraint that is related to relationships in a table, stating that a foreign key must reference an existing primary key of another entity.
Based on what I have read, I feel that referential integrity constraint is more about ensuring data integrity with regards to foreign keys, while participation constraint is more about just describing the relationships between two entities.
However, I keep having the feeling that Total Participation and Referential Integrity have a huge similarity. For example, let's say we have two tables
- Customer(CustID, CustName)
- Order(OrderID, CustID, OrderDate).
As CustID in the Order table must match a valid CustID in the Customer table, there is a referential integrity constraint here. Am I right to say that Order is also totally participating with Customer in a relationship?
