Schema.org - How can you define an object on multiple pages?

Question

Using schema.org markup, if I define many elements with the same name on several pages, but with different sets of properties defined on each page, each element only matters within the area of ​​the page on which it is defined, or is there a way to link everything their elements together to create a single, complete definition?

Answer 1

Syntax: itemid

Microdata defines the itemid attribute:

[...] to give a global identifier for an element so that it can be linked to other elements on pages elsewhere on the Internet.

A dictionary (in this case, Schema.org) would have to determine what exactly should have such a global identifier, and if or not, if several elements could have the same global identifier, and if so, how these elements should be processed .

So far, Schema.org does not define this .

An obvious assumption would be: Items (whether on the same page or on different pages, whether on the same site or on different sites) with the same itemid about the same.

Vocabulary: Unique Property Values

By specifying properties that expect unique values, consumers can (if they want) deduce that two or more elements are roughly the same.

The sameAs and url properties are suitable candidates as they can be used for any type of Schema.org.

Some more specific types define other suitable properties, such as globalLocationNumber , email , etc.