CRUD API vs REST API: Understanding the Differences and Use Cases

In the world of web development and software engineering, Application Programming Interfaces (Shortly called APIs) are a backbone for communication between different software systems. Among many APIs available today, CRUD and REST are the two most common.

What is a CRUD API?

CRUD stands for Create, Read, Update, and Delete. These are the fundamental operations performed on a database. A CRUD API is an interface that directly maps these operations to endpoints, allowing development teams to perform those actions programmatically.

Key features of a CRUD API:

• Database-oriented nature: Focuses on direct operations on database records.
• Simplistic approach: Offers straightforward methods to manage data.
• End-to-end mapping: Typically, each operation corresponds to a single endpoint, such as: POST, GET, PUT/PATCH, DELETE.

In terms of use cases, CRUD APIs are best for internal tools that need to manage databases. They can also be used in prototypes and MVPs where rapid database operations are required. In general, CRUD APIs will suit apps with simple and data-centric needs.

What is a REST API?

Now lets move to Representational State Transfer (shortly REST). It is technically an architectural style for building APIs. REST APIs are designed to adhere to specific principles, making them stateless, scalable, and flexible.

Key principles of REST API:

• Resource-based nature: Focuses on resources rather than database records. A unique URI identifies each resource.
• Stateless: Each request from the client contains all the necessary information to process it without relying on the stored context of the server.
• Uniform Interface: Defines a consistent way to interact with resources, usually via HTTP methods (GET, POST, PUT, DELETE).
• Layered System: Allows for scalability and modularity by separating the client and server concerns.

In terms of use cases, REST is used for exposing services to external clients third-party integrations and mobile apps). REST can be used in microservices architecture where there is a need for modular and stateless design.REST is generally a good choice for apps that require scalability and flexibility.

CRUD API vs REST API: key differences

Architectural style vs operations

CRUD focuses on the set of operations that need to be performed for data management. REST focuses on the architectural style used to design web services.

Statefulness vs stateless

CRUD operations need to keep track of each record’s state in the database, which is often resource-intensive and complex. REST is stateless, so there is no record of interactions and each  new request is treated as its own transaction.

Data formats and communication

CRUD operations can be performed in any needed format. REST operations require data to be transferred using formats like JSON or XML.

Flexibility and scalability

CRUD is rigid in terms of data management. REST is more flexible, offering developers a variety of options.

What about practical implementation examples?

Let's start with the CRUD API. In our example, we suggest we manage a database of books:

• POST /books: Creates a new book record.
• GET /books: Retrieves all books.
• GET /books/:id: Retrieves a specific book by its ID.
• PUT /books/:id: Updates the book with the given ID.
• DELETE /books/:id: Deletes the book with the given ID.

Now, an example of a REST API with the same books database:

• GET /books: Retrieves a list of books.
• GET /books/:id: Retrieves details of a specific book.
• POST /books: Adds a new book.
• PUT /books/:id: Updates an existing book.
• DELETE /books/:id: Removes a book from the collection.

Pros and cons of REST

• REST has a more structured approach to handling API requests compared to CRUD.
• Its key benefit is flexibility.
• REST is highly scalable and easy to maintain.
• It also requires a significant level of expertise for correct implementation.

Pros and cons of CRUD

• CRUD has a simple and straightforward approach to data management.
• It allows developers to easily manage data in any database system with no worries about the underlying structure of the database.
• It doesn't provide a structured approach to handling API requests.
• CRUD can be vulnerable to security issues.

Wrapping up

While CRUD APIs and REST APIs share some similarities, their differences lie in focus, scalability, and complexity. CRUD APIs are perfect for simple, database-oriented tasks, while REST APIs excel in resource-driven, scalable architectures. Low-code platforms like UI Bakery bridge the gap between simplicity and functionality, enabling businesses to easily create CRUD and REST APIs.