Smalyshev added a comment. In https://phabricator.wikimedia.org/T88549#1022562, @Fceller wrote:
> Still, I must admit that I'm not familiar with the internal data model of > Wikipedia. I've checked with George Washington (Q23) that he as a lot of > properties associated with him. However, I fail to see how the traversals you > mentioned are defined. If you're interested, you can look at Titan-based data model here: https://www.mediawiki.org/wiki/Wikibase/Indexing/Data_Model but in simpler terms, each entity (like Q23, aka George Washington) has a number of statements about it (which are something like "born in", "instance of", "part of", "located in", "served in office as", "cause of death", etc. - these are https://phabricator.wikimedia.org/P31, etc.). These statements have main value - which can be a scalar value or a link to another entity. The statement can also have qualifiers (i.e. when it happened, where it happened, etc.) and references (i.e. where do we know it from, when that data was retrieved, etc.) The search may involve both traversals of unknown length (i.e. going from specific place to a country), one-step traversals (i.e. knowing if the entity is "human" or "female" or the office that the person had is "the president of the USA") and filters (i.e. "it happened in 19th century", "it is located in Europe"), etc.) which can be applied to both values and qualifiers (and, potentially, references). Right now the data model is schema-neutral - i.e. it does not distinguish between claims and properties and delegates that to the query engine to figure out, for example, how to go from a town to a country. This may change in the future as we may add post-processing allowing to create additional schema links - such as direct link from a town to a country - which is not present in the source data (i.e. Wikidata). This, however, will never cover all queries as any set of properties can be queried against and any path can be traversed. So, we need a model that would allow us to support such lookups. Understandably, some of them would be easier to do and some harder, so we need a model that makes frequent cases easy/fast and complex cases possible. TASK DETAIL https://phabricator.wikimedia.org/T88549 REPLY HANDLER ACTIONS Reply to comment or attach files, or !close, !claim, !unsubscribe or !assign <username>. EMAIL PREFERENCES https://phabricator.wikimedia.org/settings/panel/emailpreferences/ To: Smalyshev Cc: Neunhoef, Fceller, JanZerebecki, Aklapper, Manybubbles, jkroll, Smalyshev, Wikidata-bugs, aude, GWicke, daniel _______________________________________________ Wikidata-bugs mailing list [email protected] https://lists.wikimedia.org/mailman/listinfo/wikidata-bugs
