A database is an organized collection of structured data stored and managed by a Database Management System (DBMS) so applications and users can create, read, update, and delete records efficiently. Databases hold the base tables that views query, enforce schemas and constraints, and provide transactional guarantees, indexing, and access control so multiple clients can work with the same data reliably. Databases may be relational, where data is stored in tables with rows and columns and relationships expressed through keys, or non-relational, using document, key-value, columnar, or graph models optimized for different workloads.
A view is a named, saved SQL query that behaves like a virtual table inside a database. It presents the result set of a SELECT statement so users and applications can query it with the same syntax used for ordinary tables, while the view itself does not permanently store the underlying data in most systems. Views provide an abstraction layer over one or more base tables or other views, hiding join logic, filters, and calculations from callers and centralizing complex query logic inside the database.
Views are used for simplifying queries, enforcing security and access control, and providing consistent interfaces across changing schemas. A developer can expose only selected columns or rows through a view, preventing direct access to sensitive columns in base tables. Views also let DBAs and developers encapsulate recurring joins, aggregations, or business rules so reports and apps use a stable, well-documented interface instead of repeatedly copying complex SQL logic into client code. Materialized views are a special case where the view’s results are stored on disk to improve performance at the cost of refresh complexity.
Views are managed objects inside a database and have metadata such as owning schema, creation date, and definition text; many database systems let you inspect a view’s SQL definition and its dependencies so you can understand which tables and columns feed the view. When underlying objects are renamed or altered, the view may need updating to remain valid, and Database Administrators (DBAs) commonly query system catalogs to retrieve a view’s definition or dependent objects for maintenance and auditing.
A DBMS centralizes data definition, storage, and query execution so a view can present a virtual table derived from one or more base tables without physically duplicating data, while materialized views optionally persist results for performance. Databases also provide tools for backup, recovery, and auditing so changes visible through views are traceable and maintainable. Designers use databases to encapsulate business rules, normalize to reduce redundancy, or denormalise for read performance depending on access patterns. Views then act as stable, permissionable interfaces that simplify complex joins and enforce security, but hide evolving schema details from clients.
Learn more from freecodecamp.org:
Learn Relational Database Basics – Key Concepts for Beginners