Use Cases of PUT vs PATCH Methods

When learning about APIs and web development, beginners often get confused between PUT and PATCH, especially in the context of CRUD operations (Create, Read, Update, and Delete). While both methods are used to update resources, they work in fundamentally different ways.

At first glance, it might seem logical to group PUT and PATCH together, since both modify existing data. However, the difference lies in how they apply changes. PUT replaces the entire resource with a new version, meaning you must send the full updated object, even if only one field has changed. On the other hand, PATCH applies partial updates, allowing you to modify only specific fields without affecting the rest of the resource.

This distinction is crucial when working with APIs, as PUT can overwrite existing data, while PATCH makes minimal changes. Choosing the right method depends on whether you need a full replacement or a partial modification. In this quick blog, we will explore these differences in more detail based on HTTP specifications and real-world use cases.

What is PUT?

The PUT method is used to update an entire resource at a specific URL. When a client sends a PUT request, it provides all the data necessary to replace the existing resource. If the resource already exists, it is completely overwritten with the new data. If it does not exist, the server may create it, provided the URI is defined.

In simple terms, PUT replaces the entire resource with the data sent in the request. If any fields are missing in the request, they might be removed from the existing resource. This makes PUT different from PATCH, which only updates specific fields instead of replacing the whole resource.

For example, if you send a PUT request to update a user profile and only include the name field, but not the email or phone number, the server may remove the missing fields if not handled properly. That’s why PUT should be used when updating complete resources, not for small modifications.

What is PATCH?

The PATCH method is used to partially update a resource at a specific URL. Unlike PUT, which replaces the entire resource, PATCH allows clients to send only the specific fields they want to update, leaving the rest of the resource unchanged.

For example, if a user wants to update just their first name in a database, they only need to send the first name field in the PATCH request. The server then applies this change without modifying other fields like email or phone number.

This makes PATCH more efficient when working with large resources, as it reduces unnecessary data transfer and prevents accidental data loss. PATCH is especially useful in APIs where updates are frequent, and only small changes are needed at a time.

What Are The Differences Between PUT And PATCH?

The only similarity between PUT and PATCH is that both are used to update resources at a specific location. However, they work differently in how they process the update.

When a PUT request is made, the client sends a complete version of the resource, replacing whatever exists on the server. If any fields are missing in the request, they may be deleted unless handled properly. Essentially, PUT treats the update as a full replacement.

On the other hand, a PATCH request contains only the specific fields that need to be updated. Instead of replacing the entire resource, PATCH modifies only the specified fields, leaving everything else untouched. This makes PATCH more efficient for small updates.

Another key difference is idempotency. PUT is always idempotent, meaning if the same request is sent multiple times, the result will be the same. PATCH, however, is not necessarily idempotent—repeating the request could lead to different results depending on how it is implemented. However, in some cases, PATCH can be idempotent if designed that way.

In summary, use PUT when updating the entire resource and use PATCH when making partial updates to avoid unnecessary data loss and improve efficiency.

Real-World Use Cases of PUT and PATCH

Understanding when to use PUT and PATCH is crucial for designing efficient APIs. Here’s how they are applied in real-world scenarios:

When to Use PUT

PUT is ideal when updating an entire resource or ensuring that a resource is completely replaced with a new version.

• User Profile Update: If an application allows users to update their profile information (name, email, phone, etc.), and the system expects the client to send the entire updated profile, PUT is the right choice. If a field is missing in the request, the API might replace it with null or default values.

• Product Information Update: In an e-commerce app, when an admin updates a product listing (title, description, price, stock, etc.), a PUT request can replace the entire product object to ensure all fields are updated correctly.

When to Use PATCH

PATCH is best for making partial updates where only specific fields need to be modified.

• Changing a User’s Email: If a user wants to update only their email address, sending a PATCH request with just the new email field is more efficient than sending the entire profile.

• Updating Order Status: In an order management system, when an order moves from “Processing” to “Shipped”, PATCH can be used to update just the status field instead of resending all order details.

• Modifying Blog Post Content: If a blogging platform allows users to edit only the title or content of a post while keeping metadata unchanged, PATCH is a better choice for efficiency.

Frequently Asked Questions (FAQs)

What is the difference between PATCH and PUT?

With a PUT request, the server modifies the resource identified by the Request-URI. With a PATCH request, the server places or updates only specific parts of a resource without changing other aspects. These are the main differences.

What is the difference between POST PUT and PATCH?

If you are curious about the difference between POST PUT and PATCH, here is what you need to know. PUT is always used for creating a resource, while PUT checks if a resource exists. Then it updates, or else it creates a new resource.

Is PUT the same as UPDATE?

No. They are similar in some ways, but different in many others. PUT allows the server to modify the resource identified by the Request-URI, while PATCH lets the server place updates only to specific parts of the resource. This means that it does not change other aspects.

Why is PUT better than PATCH?

This is because PUT handles updates by replacing the entire entity, while PATCH only updates specified fields.

Is PUT a REST API?

It is essential to understand what a RESTFul API is first. A RESTful API is an architectural style for an application program interface (API). It leverages HTTP requests to access and use data. PUT is a REST API.