Databases and normalisation

An entity is represented by what in a database?

• Table

• Row

• Column

• Cell

A record is represented by what in a database?

• Table

• Row

• Column

• Cell

Which of these are required for a relational database to meet 2nd normal form?

• Must meet 1st normal form

• All the non-key attributes must depend on the whole primary key

• All the non-key attributes must not depend on another non-key attribute

• Must meet 3rd normal form

Which of these are required for a relational database to meet 3rd normal form?

• Must meet 2nd normal form

• All the non-key attributes must depend on another non-key attribute

• All the non-key attributes must not depend on another non-key attribute

• Must meet 4th normal form

What is the purpose of normalisation?

• Eliminate redundant data

• Reduce data inconsistencies

• Produce redundant data

• Increase data inconsistencies

Which type of relationship does the ERD represent?

• One-to-many

• Many-to-many

• One-to-one

What is a composite primary key?

• A primary key that can be duplicated in the same table

• An attribute that is a primary key in another table

• A foreign key that is a primary key in more than one other table

• A primary key made up from two or more attributes

Data type used for telephone numbers

• Text

• Number

• Date/Time

• Yes/No

• Currency

What does Normalisation allow a database designer to do?

• Design their database efficiently, removing the chance of redundancy and inaccuracies. 
• Remove additional records from the tables. 
• Add as much data as they like. 
• Draw an ERD. 

A foreign key

• Links to a primary key in another table. 
• Links to another foreign key. 
• Links to another database system. 
• Should always reference a unique value in the same table.