Database Relationships

Semantic relationships take a higher and more non-specific view of the relationship.

• True

• False

What is a candidate key?

• Any attribute, or group of attributes, that can uniquely identify a tuple in a relation.

• Any attribute, or group of attributes, that has no super key subsets.

• Any attribute, or group of attributes, that has been selected to be the unique identifier of each tuple in a relation.

• A combination of two fields that together can uniquely identify a record.

Complete the sentence below.

A _____ key is an attribute of a table that matches a primary key attribute in another table to create a relationship.

• Candidate

• Primary

• Foreign

• National

A composite key is a combination of two fields that together can uniquely identify a record.

• True

• False

Complete the sentence below.

A ____________ relationship is where a single record of a table is related to a single record of another table.

• Many-to-many

• Many-to-one

• One-to-one

• One-to-many

Complete the sentence below.

________ integrity is a rule that states that every entity must have a primary key field and the values in that field must be unique to each record.

• Entity

• Primary

• True

• False

What type of relationship should we not use in our database structure?

• One-to-One

• One-to-Many

• Many-to-Many

Complete the sentence below.

A ______ key is any attribute or group of attributes, that can uniquely identify a tuple in a relation.

• minimal

• super

• higher

• fantastic

Referential Integrity is a rule states that every foreign key value must match the primary key value of a record in another table, or must be null.

• True

• False

What type of relationship is shown in this image?

• One-to-One

• One-to-Many

• Many-to-Many