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TERMINOLOGY GLOSSARY

Topics from the International Baccalaureate (IB) 2014 Computer Science Guide. 

• Database: An organised collection of data that can be accessed, managed, and updated.
• Field: A single piece of information or data within a database record.
• Record: A collection of related data fields within a database.
• Table: A collection of related records within a database.
• Entity: A person, place, thing, or concept within a database that can be uniquely identified.
• Attribute: A characteristic or property of an entity within a database.
• Query: A request for data from a database, often expressed in a specific language or format.
• Concurrency: The ability of a database management system to allow multiple users to access and modify the database at the same time.
• DBMS: Database Management System, a software system that manages the storage and organization of data within a database.
• Atomic: A database transaction that is indivisible and must be completed in its entirety or not at all.
• ACID: A set of properties that ensure database transactions are processed reliably: Atomicity, Consistency, Isolation, and Durability.

1. Atomicity: The property of a database transaction that guarantees that it is treated as a single, indivisible unit of work.
2. Consistency: The property of a database transaction that guarantees that the database remains in a valid state before and after the transaction.
3. Isolation: The property of a database transaction that guarantees that it is executed in isolation from other transactions.
4. Durability: The property of a database transaction that guarantees that once a transaction is committed, its changes are permanent and can survive system failures.

• Integrity: The property of a database that ensures the accuracy, completeness, and reliability of the data stored within it.
• Transaction: A set of operations that are executed as a single unit of work within a database.
• Validation: The process of ensuring that the data entered into a database is correct and accurate.
• Verification: The process of checking the accuracy and completeness of data stored within a database.
• Database Transaction: A sequence of operations that are executed as a single unit of work, such as inserting, updating, or deleting data within a database.
• Flat-File Database: A database system in which all the data is stored in a single table.
• Relational Database: A database system in which data is stored in multiple tables, each with its own unique key, and relationships between tables are established through keys.
• Primary Keys: A unique identifier for a record in a database table, used to establish relationships between tables.
• Foreign Keys: A field in one table that refers to the primary key of another table, used to establish relationships between tables.
• Composite Keys: A combination of two or more fields that form a unique identifier for a record in a database table.
• Candidate Keys: A field or combination of fields in a database table that could be used as the primary key.
• Bridge Table: A table used to establish a many-to-many relationship between two tables in a relational database.
• Cardinality: The number of records in a table that are related to another table in a database.
• Join Type: A method of combining records from two or more tables in a database.
• Simple Query: A query that retrieves data from a single table in a database.
• Complex Query: A query that retrieves data from multiple tables in a database using various criteria and conditions.
• Redundant Data: Data that is duplicated or repeated unnecessarily within a database.
• Referential Integrity: The consistency and accuracy of data relationships within a database, maintained through the use of primary and foreign keys.
• Normalisation: The process of organising a database to minimise redundancy and maximise efficiency.
• Transitive Dependencies: A relationship between three or more fields in a database table, in which a change in one field can affect other fields.
• Non-Key Field: A field in a database table that is not used as a primary or foreign key.
• SQL: Structured Query Language, a programming language used to manage and manipulate data in relational databases.

ALSO IN THIS TOPIC

BASIC CONCEPTS
RELATIONAL DATABASES 2.1 - 2.8
RELATIONAL DATABASES 2.9 - 2.20
DATABASE MANAGEMENT
DATABASE MODELS AND ANALYSIS
DATABASE KEY TERMINOLOGY
DATABASE ANSWERS