🔄I Thought PUT and PATCH Were the Same… I Was Wrong

Source: Dev.to

🧠 Why These HTTP Methods Matter

In REST APIs, HTTP methods are not just syntax.
They define:

• API behavior
• Client expectations
• Data integrity
• Error handling

Using the wrong method can make your API confusing, unreliable, and hard to maintain.

✏️ PUT Mapping — Full Update

PUT is used when you want to replace an entire resource.

Key idea:
PUT expects the complete object, not partial data.

If a field is missing:

• It may be overwritten
• Or reset unintentionally

That’s why PUT must be used carefully.

🧩 PATCH Mapping — Partial Update

PATCH is used when you want to update only specific fields.

Key idea:
PATCH modifies only what is provided, leaving the rest untouched.

This is extremely useful when:

• Updating a single field
• Avoiding accidental data loss
• Designing flexible APIs

Once I understood this difference, my update APIs stopped behaving strangely.

🗑️ DELETE Mapping — Remove a Resource

DELETE is used to remove a resource from the system.

Sounds simple — but here’s where many beginners (including me) go wrong.

Common mistake:

• Always returning success, even when the resource doesn’t exist

A good DELETE API should:

• Verify the resource exists
• Return meaningful responses
• Handle errors gracefully

DELETE is not just about removing data — it’s about correct API behavior.

⚠️ The Mistake I Was Making

I used to:

• Use PUT everywhere
• Ignore PATCH completely
• Treat DELETE as a dummy operation

It worked in demos — but failed in real projects.
Understanding intent behind each method changed how I design APIs.

✅ What Changed After I Got This Right

Once I used these mappings correctly:

• APIs became predictable
• Clients trusted responses
• Bugs reduced
• Code felt professional

This is where Spring Boot APIs start to feel production‑ready.

🚀 Final Thoughts

PUT, PATCH, and DELETE look simple — until you misuse them.

If you’re learning Spring Boot and your APIs feel:

• Unclear
• Inconsistent
• Hard to debug

Start here. This understanding is a major step in becoming a backend developer.