Quiz Entry - updated: 2026.10.20
How do the HTTP methods POST, PUT, GET and DELETE map to operations on data?
They map to create, update, read and delete (CRUD), the same four operations as SQL's INSERT, UPDATE, SELECT and DELETE.
| HTTP method | Database analogue | What it does to the resource |
|---|---|---|
| POST | INSERT | Creates a new resource (the server picks its URL), or more generally hands data to the server to process |
| PUT | UPDATE | Replaces the resource at the given URL with the request body, creating it if it does not exist |
| GET | SELECT | Reads the resource. It never changes it |
| DELETE | DELETE | Removes the resource |
The mapping matters for IoT because constrained protocols kept it. CoAP, the lightweight web protocol for small devices, uses the same GET, POST, PUT and DELETE over UDP, so a sensor reading is a GET and a configuration change is a PUT. A device that understands these four methods can be designed like a tiny web server: every reading, setting and actuator is a resource with a URL.
Go deeper:
MDN — HTTP request methods — every method with its exact semantics.- Wikipedia — Create, read, update and delete — the CRUD mapping across SQL, HTTP and other interfaces.