Summary GCSE AQA Computer Science - Database concepts

Database Concepts

• Database
o A structured collection of data that stores information in an organized
manner.
• Tables
o Store data in a logical format using rows and columns.
o Each table represents an entity (e.g., a person, object, or event).
• Relational Database
o A database system that links multiple tables using keys.
o Helps reduce data redundancy and inconsistency.
o Minimizes the number of updates needed when data changes.
• Entity
o Represents an object, person, item, or concept that data is stored about.
• Data
o Raw facts and values.
• Information
o Processed data that provides meaning and context.
• Data Types
o Text (Different from Python's data types).
o Integer (Whole numbers).
o Float (Decimal numbers).
o Date/Time (Stores date and time values).
o Boolean (True or False).
• Records
o Individual rows in a database table.
o Each record contains data related to a single entity.
o Each record has a unique identifier.
• Fields
o Columns in a database table.
o Each field stores a specific attribute of the entity.
o Field names are used to describe the type of data in the column.
• Identifier
o A unique value (such as an ID) that distinguishes one record from
another.
• Data Inconsistency
o Occurs when the same data is formatted differently across records.
• Data Redundancy
o Happens when the same data is stored multiple times in different places.