What is a database?
An organized collection of data, typically stored and accessed electronically, managed by a database management system (DBMS).
What does DBMS stand for?
Database Management System – the software that interacts with users, applications, and the database to capture and analyze data.
Name three components that make up a database system.
The database itself, the DBMS, and associated applications.
What is a table in a relational database?
A set of data organized into rows and columns, where each row is a record and each column is a field.
Define 'record' in the context of databases.
A single row in a table that contains data about one specific item or entity, made up of fields.
Define 'field' in the context of databases.
A column in a table that holds a specific type of data for each record, such as a name or age.
Why use a database instead of a long list or spreadsheet?
Databases can handle large amounts of data efficiently, allow complex queries, reduce data redundancy, and maintain data integrity.
What is a query in a database?
A request to retrieve or manipulate data based on specific criteria, often written in SQL.
What does SQL stand for?
Structured Query Language – the standard language for writing and querying relational databases.
Name three common data types used in databases.
Text (or string), number (integer or decimal), and date/time.
What is data validation?
Rules applied to fields to ensure data is accurate and reasonable, like checking that a date is in the correct format or an age is positive.
Give an example of a validation rule for an 'Age' field.
Age must be a number between 0 and 120.
What is sorting in a database?
Arranging records in a specific order, such as alphabetical or numerical, based on one or more fields.
What is filtering in a database?
Displaying only records that meet certain criteria, using a query or filter condition.
What is a primary key?
A field (or combination of fields) that uniquely identifies each record in a table, ensuring no duplicates.
Why is a primary key important?
It ensures each record can be uniquely identified, which is essential for efficient searching and linking tables.
What is a relational database?
A database that organizes data into multiple tables that are linked by common fields, using the relational model.
Who proposed the relational model and when?
Edgar F. Codd in 1970.
What is NoSQL?
A category of non-relational databases that use different query languages and are designed for large-scale, flexible data storage.
Give two examples of relational database management systems.
MySQL and Microsoft SQL Server (also Oracle, IBM Db2).
What is a database management system (DBMS) used for?
To create, manage, and manipulate databases, including data definition, updates, retrieval, and administration.
What is data integrity?
The accuracy and consistency of data stored in a database, maintained through constraints and validation.
Name one everyday example of a database.
A school's student records system, a library catalog, or a phone contact list.
What is the difference between a database and a DBMS?
A database is the collection of data itself, while a DBMS is the software used to manage and interact with that data.