Databases - Design - 1 Flashcards
How many entities does one table hold the attributes for?
1
When does one to many cardinality exist?
When one entity can be present in many different instances of another entity.
What is a Data Dictionary and what do they contain?
They are used to plan information and includes the name and description of the attributes (fields) in each entity(table) within a database.
What are entities?
A place where information about a concept is collected – a table. They are made up of attributes.
What are attributes?
They describe the details of an entity (field)
What are validation checks used for?
They ensure data is allowable, making it harder to make mistakes.
Name and describe the 4 types of validation checks
- Range – ensures data is between a lower and upper limit
- Restricted Choice – limits the user to a list of options.
- Length Check – restricts number of characters that can be entered.
- Presence Check – ensures that the field is not left blank
List the 6 laws in the GDPR act
The implications for individuals and business of the UK GDPR legislation means that the data they hold must be:
- processed lawfully, fairly and in a transparent manner in relation to individuals
- used for the declared purpose only
- limited to the data needed for the declared purpose
- accurate
- not kept for longer than necessary
- held securely
What is a relational database?
A database that is usually arranged across many tables, which can be joined via a primary or foreign key.