Section 10 Flashcards
What is a Relational Database?
A method of creating a database using tables of related data, with relationships between the tables.
What is a Table?
A method for implementing an entity and attributes as a group of related data.
What is an Entity?
An object about which data will be stored.
What is an Attribute?
A characteristics or piece of information about an entity, which would be stored as a field in a relational database.
What is an Entity relationship diagram?
A visual method of describing relationships between entities.
What is a Primary key?
An attribute that can be used to uniquely identify every record within a table.
What is an Entity identifier?
An attribute which can uniquely identify each instance of an entity.
What is a Foreign key?
An attribute in a table that is a primary key in another table and us used to link tables together.
What is Normalisation?
The process of ensuring that a relational database is structured efficiently.
What is Structured query language (SQL)?
A specialised programming language for manipulating databases.
What is Syntax?
The rules of how words are used within a given language.
What is a Query?
A search or sort carried out on data that retrieves the answer to a question.
What is a Client-server database?
A way of implementing a database where the database is put into a server and various users can access it from their workstations. The processing, for example, running a query, will take place on the server.
What is a Database management system?
Software that enables the management of all aspects of a database including adding, updating and querying data.
What is Record locks?
A technique to temporarily prevent access to certain records held on a database.
What is Sterialisation?
A technique to ensure that only one transaction at a time is executed from multiple users on a database.
What is Timestamp ordering?
A technique to ensure multiple users can execute commands on a shared database based on the timestamp of when the data was last written to or read from.
What is Commitment ordering?
A technique to ensure concurrent transactions on a shared database are executed based on a the timestamp of when the request is made and also the precedence the request takes over other simultaneous requests.
What is Big data?
A generic term for large or complex datasets that are difficult to store and analyse.
What is Modelling?
Recreating a real life situation on a computer.
Graph Schema (database)?
A method of defining a database in terms of nodes, edges and properties.
What is a Node (database)?
In database modelling, it is an entity.
What are properties (database)?
In database modelling, it is items of information stored within each each entity.
What is an Edge (database)?
In a database graph schema, it refers to the link and relationship between two nodes.
What is Distributed processing/computing?
The principle of spreading large and complex tasks over a number of computers or servers.
What is a Distributed program?
A program specifically written to be used in a distributed processing environment.
What is Functional programming
A programming paradigm that uses functions to create programs.
What is a Variable?
A data item whose value will change as the program is run.
What is meant by the term ‘Mutable’
Changeable.
What is meant by the state of a variable?
The Value that is currently stored in that variable.
What does the term ‘Side effects’ mean in context to programming?
In programming it refers to the fact that the value contained within a variable will change as the program is run, which has implications for other parts of the program.
what is an Imperative language?
A language based on giving the computer commands or procedures to follow.
What is Object-oriented programming?
A programming paradigm that encapsulates instructions and data together into objects.
What is a Function?
A subroutine that returns a single value.
What is meant by the term ‘Concurrence’?
The concept of two users trying to access the same data item at the same time.
