Difference between views handler and views plugin?

Question

What are the main differences between view handlers and view plugins?

I checked the documentations for view handlers and view plugins, but I find them quite similar.

Can anyone show me what a view handler can do that a view plugin cannot?

Answer 1

The difference is summarized in the first sentence on About Views plugins:

In Views, a plugin is a bit like a handler, but plugins are not directly responsible for building the query. Instead, they are objects that are used to display the view or make other modifications.

A view handler is implemented using a class derived from the views_handler class, which has methods to build the query, or to alter the result obtained from a query, such as:

• views_handler::get_join()
• views_handler::pre_query()
• views_handler::sanitize_output()
• views_handler::post_execute()
• views_handler::placeholder()

On the other hand, the views_plugin class has only a method that is related to the query: views_plugin::query().