What action does @HttpPatch perform in a Salesforce API?

The action performed by @HttpPatch in a Salesforce API is to update fields on existing records. This method is specifically designed to apply partial updates to resource representations. When a client sends a PATCH request, it typically includes only the fields that need to be updated, rather than requiring the entire resource representation to be sent.

In the context of Salesforce, this means you can modify specific attributes of a record without altering all the data. This capability supports efficient data management and allows for flexible updates where only necessary information is transmitted, reducing bandwidth usage and minimizing processing time.

Understanding this functionality is important for integration developers utilizing RESTful services within Salesforce, as it allows for streamlined update processes and enhances overall API efficiency.