Databases and SQL

A database is a large collection of related data and computerised ones are used because....

• Paper filing cabinets are outdated and take up too much room

• Computerised databases are much better then paper ones

• Computerised databases take up less space, can be easily edited and are faster at searching and sorting information

• Computerised databases are much more efficient than paper ones, there are fewer errors and its faster to find all the data you need

Databases have a structure that has

• A file which is made up of records and each record has a number of fields

• A table which is the file. It has records and fields in the table.

• Multiple tables each with their own file, records and fields

Which best explains the differences between a flat file and a relational database?

• Flat files only have one table

• Flat files only have one table and are prone to data inconsistencies unlike relational databases

• Relational databases have multiple tables to avoid data anomalies which are commonplace in flat file databases

Validation of data is conducted to ensure

• That any data entered is correct

• That any data entered is accurate

• That any data entered is acceptable and sensible

• That any data entered is accurate and sensible

A foreign key

• is a primary key in its own table and used in a second table to create a link between them

• is a field in both tables used to create a link between them

• is a primary key used in two tables to create a link between them

• is where the primary key is made up of two or more fields

Which of the following is a category of object, person, event or a thing of interest to an organisation?

• Flat File
• Entity
• Attribute
• Primary key

What is used to present the relationship between entities in a database?

• ER Diagram
• Referential integrity
• Primary Key
• Foreign Key

Which type of key is a unique identifier?

• Primary Key
• Foreign Key
• Secondary Key

Which best describes a characteristic about an entity 

• Primary Key
• Secondary Key
• Attribute
• Record

Which type of relationship best describes the following?

Head teacher who runs a School

• One to one
• Many to many
• One to many