Understanding The Concepts of Databases (AQA)

Database

A structured collection of data stored and accessed electronically, ensuring data integrity, security, and concurrent access to multiple users.

Relational Database

A type of database that stores data in a structured format using tables related through keys, introduced by E.F. Codd in 1970.

Table

A collection of related data entries organized in rows and columns.

Record

A single, complete set of related data in a table.

Field

A single piece of data or attribute for each record in a table.

Primary Key

A unique identifier for each record in a table, ensuring unique identification.

Foreign Key

A field in one table that uniquely identifies a row in another table, creating a relationship between them.

Data Inconsistency

Occurs when different copies of the same data do not match due to lack of synchronization.

Data Redundancy

Occurs when the same data is stored in multiple places, leading to inefficiency and inconsistency.

Normalization

Organizing data into logical units (tables) and establishing relationships between them using primary and foreign keys.

ACID Transactions

Transactions that adhere to ACID properties (Atomicity, Consistency, Isolation, Durability) to maintain data consistency.

Constraints

Rules enforced at the database level to prevent invalid or inconsistent data, maintaining data integrity.

Single Source of Truth

Storing data in normalized tables to ensure there is only one authoritative source for each piece of data.

Efficient Storage

Storing data once and referencing it using foreign keys when needed to reduce redundancy.