Sofia Relational Databases Unit 5 Milestone 5
What type of key can be used in an associative entity? - A composite primary key
Which tables are lookup tables? - Category, AddressType, PhoneType
What is true about normalization? - It may decrease performance due to additional joins.
Is this dataset in 2NF or not? If not, why not? - No, there are columns that are not dependent on the
primary key.
What is wrong with the following ERD meant to show a relationship between two entities? - There is
nothing wrong with the ERD.
What could be a reason to denormalize a database? - The database may require us to value
performance over storage and redundancy issues.
What is a key feature of fourth normal form? - It should already satisfy the properties of BCNF.
Identify the normal form in which all of the attributes are set up to be dependent on the primary key. -
1NF
What is used to indicate a weak relationship in an ERD in Crow's Foot notation? - Dashed line between
entities
Is this dataset in 3NF? If not, why not? - Yes, it is in 3NF.
What type of connection trap could be created due to a convergence of two one-to-many relationships
on a single table? - Chasm trap
What is the relationship between tables Movie and Rating? - 1:M
