What is a Database?
A database is an organized collection of information that can be stored, managed, searched, and updated. In a business setting, a database might store customer names, addresses, purchase histories, support tickets, and other records that a company needs to access over time. Oracle defines a database as an organized collection of information used to store and retrieve related data for applications.
Many databases organize information in tables made up of rows and columns. Unlike a spreadsheet, which is often used for smaller or less complex datasets, a database is designed to manage larger amounts of structured information, support queries, and allow multiple users or applications to work with the data. For example, a sales team, customer service team, and billing system might all rely on the same customer database.
A database management system, or DBMS, is the software used to create, update, organize, secure, and retrieve information from a database. Common examples include Oracle Database, Microsoft SQL Server, MySQL, and PostgreSQL. Together, a database and its DBMS help organizations keep data organized, searchable, and usable for reporting, operations, analytics, and decision-making.
Who Uses a Database?
Businesses can use databases to better organize and use their data, which has a number of benefits. Databases can help businesses assess performance and make informed decisions. A business might use its database to build better relationships with customers, implement more effective marketing, assess the performance of new products or offers, and much more.
Databases fulfill many roles, some of which may benefit from basic or even advanced database skills.
For instance, marketing professionals may use databases to oversee marketing campaigns, nurses might use electronic healthcare record databases to manage patient data, and customer service representatives may access and input customer data through databases.
Prospective students interested in these roles may also want to explore related career paths, such as data engineer and data architect, which involve designing and building the broader data infrastructure that supports databases.
Different Database Types
There are many types of databases, and they all work in different ways. The best type of database for a business will depend on its focus and how it stores and uses data. Additionally, as some businesses grow, they may need to use multiple types of databases for different applications to simplify maintenance and debugging.
Many variables come into play when a business chooses the right database(s). Some common types include:
- Relational databases.
- Distributed databases.
- Object-oriented databases.
- Open-source databases.
- Cloud databases.
- Vector databases.
Relational Database
Relational databases store information in tables with rows and columns. These databases allow multiple users to access data simultaneously, support data recovery after a failure, and operate across multiple platforms. MySQL, Oracle, Microsoft SQL Server, and PostgreSQL are all common examples of relational databases. Relational databases remain widely used by organizations of all sizes, from startups to large enterprises, and serve as the foundation for SQL, the query language that underpins much of modern data analysis.
Distributed Database
While many databases consist of a centralized collection of data, distributed databases take a different approach. These databases consist of two or more files stored in different locations — sometimes on completely different networks. Users can still access and edit data, but the files must be synchronized. This type of database offers a major advantage in resilience: if one site fails, data can still be retrieved from another. Examples of distributed databases include Apache Cassandra, Amazon DynamoDB, and Google Spanner.
Object-Oriented Database
An object-oriented database stores data as objects and is based on a type of object-oriented programming like C++, Java, Python or JavaScript. Object databases offer many benefits, including the ability to handle complex data, quick access to that data and more efficient coding than other database types. Common object-oriented databases include Cache, ConceptBase, ObjectDB Object Database and Versant Object Database. These types of databases are often used in situations where fast results and calculations are necessary, such as in telecommunications, molecular science and 3D architecture and engineering.
Open-Source Databases
Open-source databases are made available to the public, often at no cost, allowing businesses to access and modify the source code to customize them. Many open-source databases offer robust data security, collaborative features, and cross-platform support. The flexibility and customization options make open-source databases practical for a wide array of businesses. Popular examples include PostgreSQL, MySQL, and MongoDB.
Cloud Databases
Cloud databases are hosted on a cloud computing platform. That cloud platform can be a public, private or hybrid platform. Cloud databases depend less on hardware, and as a result tend to be much easier to scale. Because businesses don’t need to focus on expensive upgrades, cloud databases are often more economical. They may also offer enhanced security. Common cloud databases include Oracle, Amazon Web Services, Microsoft Azure and Google Cloud Platform.
Vector Databases
A relatively new and rapidly growing database type, vector databases are purpose-built to store and query high-dimensional data representations called embeddings, numerical arrays that capture the semantic meaning of content like text, images, and audio. They are a foundational component of modern AI applications, enabling fast similarity search across large volumes of unstructured data. Vector databases power use cases such as AI chatbots, recommendation systems, and retrieval-augmented generation (RAG), a technique that connects large language models (LLMs) to proprietary data sources. Leading platforms include Pinecone, Weaviate, Milvus, and Chroma, as well as vector search capabilities now integrated into major cloud databases, including Google AlloyDB, AWS OpenSearch, and Azure SQL. According to IBM, vector database adoption grew 377 percent year over year as of 2025, reflecting its central role in the generative AI era.
AI and the Evolving Database Landscape
Artificial intelligence is reshaping how databases are designed, managed, and used. As organizations adopt AI-powered applications at scale, databases must support new types of data — particularly the unstructured content (text, images, audio, video) that AI models consume and generate.
One significant development is the integration of vector search capabilities directly into traditional database platforms. Major cloud providers, including Google, AWS, and Microsoft, have embedded vector indexing into their existing relational and NoSQL offerings, reducing the need for separate AI-specific infrastructure. This trend reflects a broader shift toward what industry analysts describe as a unified "data and AI control plane," where a single database environment can serve transactional, analytical, and AI workloads simultaneously.
AI is also influencing the database administrator role itself. According to the BLS, the Occupational Outlook Handbook from May 2024 states that as organizations adopt AI to process and analyze data, database architects will be increasingly critical for designing and securing the infrastructure that supports AI systems. BLS projects that employment of database administrators and architects will grow 4 percent from 2024 to 2034, about as fast as the average for all occupations. Over the decade, an average of 7,800 openings for database administrators and architects are projected each year.
For students considering graduate programs in data science or data engineering, understanding how databases interact with machine learning pipelines, cloud platforms, and AI systems is increasingly important coursework. Many now include database systems, data engineering, and cloud infrastructure in the core curriculum.
Database Learning Databases
The following resources can help readers learn database fundamentals, SQL, and commonly used database management systems.
Our database and data science guides
- What Is a Database?: Our beginner-friendly overview of databases, database management systems, and common database tools.
- Using SQL for Data Science: Our introduction to SQL and how it is used to query, update, and manage structured data.
- How to Learn MySQL: Our guide to MySQL, relational databases, and SQL learning resources.
- How to Become a Data Engineer: Our career-focused guide for readers interested in data pipelines, data architecture, and database-related technical roles.
- Data Science Resource Hub: Our broader collection of learning resources covering data science, analytics, programming, and related technical topics.
Official database and SQL tutorials
- PostgreSQL Tutorial by PostgreSQL: Official PostgreSQL documentation introducing relational database concepts and SQL.
- MySQL 8.4 Tutorial by Oracle: Official MySQL documentation covering how to create and use a basic MySQL database.
- SQL Server Educational SQL Resources by Microsoft Learn: Microsoft tutorials, quickstarts, and training resources for SQL Server and Azure SQL Database.
- SQL Server Technical Documentation by Microsoft Learn: Microsoft documentation for SQL Server setup, development, administration, and related products.
- Oracle FreeSQL by Oracle: A free Oracle resource for practicing SQL in a browser-based environment.
- Oracle Database 23ai SQL Features Tutorial by Oracle: An Oracle tutorial for learners who want to explore newer SQL features in Oracle Database 23ai.
Additional practice and reference resources
- W3Schools SQL Tutorial by W3Schools: A beginner-friendly SQL reference with examples and short exercises.
- SQL Server Tips, Articles and Training by MSSQLTips: A SQL Server learning site with tutorials, articles, webinars, and community resources.
Information last updated: July 2021