Databases Flashcards
Data
consistency
Ensuring that data is correct after it has been processed
Data
redundancy
When data appears unnecessarily more than once in a database
Data
independence
When the structure of the database with its data is kept separately from the applications that use the data.
Relational
Database
A group of tables linked together by primary and foreign keys
Primary Key
A field in a table that uniquely identifies each record
Foreign Key
A field in one table that references the primary key field in another table
Compound key
A primary key that is made up of multiple fields and together they uniquely identify each record.
Database
Management
System
A DBMS is designed to allow the definition, creation, querying, updating, and administration of databases.
Table Index
An index is a separate file that stores addresses to blocks or direct link to the complete row of data from a table to enable fast searching.
Entity
An object in a system that we want to model and store data about
Database view
A view is the result set of a stored query on the data. A view contains rows and columns, just like a real table. The fields in a view are fields from one or more real
tables in the database
Object Oriented
Database
Uses objects to model the required behaviours rather than tables
Distributed
Database
Data is stored in a number of computers at different physical locations but it appears as one logical database.
Link
Connection between two tables by primary/foreign keys
Relation
A set of attributes modelling an entity (table)
