Help:Structure

To understand better the way we gather and display the information, it is helpful to have an idea about the technical structure behind the Canon-base system. In this chapter, we describe in short the concepts and the terminology used without (we hope) to going to much into technical details.

The Canonbase structure

The underlaying structure of the Canon-base is a triplet database, similar to and built with Wikidata software. It consists of items that are connected with properties through statements. We can also add properties to an item that just describe the item in detail. In human language, we have a large box of “things” that have properties and are connected to each other by relations.

For example:

“Bill Der” is an item, the “somewhere theatre” is an item.
We know about “Bill Der” that:
* He is born on the second of February 1921
These are properties of “Bill Der”  
We also know about the “somewhere theatre”:
* That it is build in 1954
* That the architect was named “Bill Der”
The fact that we know the architect is a property that relates “Bill Der” to the “somewhere theatre”

Example

Statements can connect two “things”, so “Bill Der” is the architect of “somewhere theatre”. Statements always have three elements, an item, a property and a value, therefore we call them triplets.

Each item has it’s own page, defined by a Q-number. So when we add a statement to an item, we only need to add two things: the property and a value.

For example:

If I  am working on the page of the “somewhere theatre” I can add the property “architect” and give it a value “Bill Der”. This relates the two items.
If I  am working in the page of the “somewhere theatre” I can also add the property “building date” to the item and give it the value 1954. This does not relate the item to something else, but just stores the information.

Of course we are not limited to adding one statement to an item. We can add multiple statements and multiple values to one statement.

For example:

“Bill Der” also build the “in another place theatre”, his occupation is architect, and he is born in “some country”. 
We also know that “Desi Gner” is also an architect. We can add all these properties in statements now.

Example

By building all these statements, we start to see all kinds of relations and we can structure information; for example, we will be able to make a list of architects.

Items

Items are concepts, things in the widest sense of the word. The concepts are language independent. A theatre (building) is a concept that exists in many languages, expressed by many different words, but it will always have the same meaning.

On the other hand “theatre” can refer to an artform as well a building. These are two different concepts, expressed by the same word (in English). So they will also be two different items.

Each concept / item has its unique Q number; this is the number of the page and also appears in the URL.

The concept is defined by a label, a description and one or more also known as labels.

• Label is the most common name for the concept in a specific language .
• Description is a statement that describes the concept so that there can be no misunderstanding about the meaning and that the difference with other concepts is clear.
• Also known as gives alternative or historic terms for the concept.

Labels and descriptions of a concept occur in as many languages as the system knows and that have been added.

Statements

Statements connect an item through a property with a value or another item. The first item is always the page you are looking at.

For example, on the page “somewhere theatre” there will be a property (architect) with a value “Bill Der”.

Some statements can have multiple values, for example “Bill Der” is an “architect”, but he is also an “author”, because he writes in the architects' magazine.

Properties

Properties can link or contain information.

In case of a link the information expected is “item”.

Otherwise the property expects a specific type of information.

• Time – date
• Geographic information
• Monolingual information (can be filled in multiple languages)
• Language independent information.
• Value, amount, number
• External identifier (a URI, code part of a URL)

Qualifiers

In some cases a triplet is not enough to make a relation sufficiently specific.

For example “Bill Der” lived in “somecountry” from 1921 until 1951. These dates are related directly to the place he lived. Probably he lived later in “anothercountry” from 1951 till 1961. So the dates are not related to him, but to him living somewhere.

In this case, we use qualifiers. We add the dates as extra information to a triplet. For example we add to the item “Bill Der”:

• lived in “somecountry”
  • from 1921
  • until 1951
• lived in “anothercountry”
  • from 1951
  • until 1961

Inverse property labels (and Inverse properties)

If “Bill Der” [is the architect of] the “somewhere theatre”, this also means that the “somewhere theatre” [is designed by] “Bill Der”. So [is the architect of] is an inverse property of [is designed by].

Wikidata does not know this concept in it’s representation. In Canonbase, we added the representation. If an item is mentioned in a property, this will be visible in the item as a inverse property label. But if you want to change it, you have to edit in the related item.

We generally avoid having inverse properties in both directions, but we have made a property for the most obvious cases. In exceptional cases we have properties in both directions.

Language

Even if concepts are language independent, we need language to express them. We use English as the root language, so in theory every item should exist at least in English.

Language setting

When you go to the website, it will automatically switch to the language in your browser or to English if your language is not (yet) supported. The interface, the properties and the most important items will be in that language, but you will also see the other languages.

If you prefer another language as the basic language, you can always adapt the setting, clicking the icon top-left of the page.

Names of persons, theatres, sources, etc. are not translated, so you will find them in English. Names of geographical entities are only translated if there is a generally acknowledged translation.

Extra features

We incorporated some extra features to the database. These will support a better understanding or help you find your way.

• Wikipages: a text-based section at the top of an item's page, just like a monolingual wikipage.
• Lists and trees: showing underlaying information in an organised and structured format.
• Timelines: showing dates in a graphical format
• Maps: showing underlaying information on a map.
• Wikidata: retrieving information from the main wikidata platform.