On 04.02.2016 18:59, Daniel Kinzler wrote:
Am 04.02.2016 um 08:03 schrieb Markus Krötzsch:
Data model updates are costly. Don't make
them on a week's notice, without prior
discussion, and without having any documentation ready to give to data users. It
would also be good to announce breaking technical changes more prominently on
wikidata-tech as well.
These have been discussed for months, if not years. Especially identifiers.
Citation needed ;-) Note that my emails were about math, not about the
identifiers. Also, discussing about something is not enough. In the end,
you need to give us the technical details so we can fix our tools. I
knew that you planned to introduce identifier types, but I still don't
know the RDF IRI for this new type.
I do not consider adding new data types a breaking change. Converting existing
properties to a different data type is a breaking change to the data-set, not to
the model or the software.
No, sorry, this is just wrong. The datatypes are part of the model, not
of the data. Changing the format of JSON to include new, hitherto
unknown types might break a tool (and not break others). It will depend
on the function of the tool (and its implementation technique) but some
For example, a tool that converts Wikidata to RDF will have a problem if
it encounters something that it cannot translate. This is hard to
recover from, since you cannot even declare the exported property as a
property at all unless you probe your data to find hints in the form of
values that use this data (I don't think any existing export tool would
work like this). As a result, you fail to export a significant part of
the property definitions, which makes the dumps invalid for OWL, or you
have to omit big parts of the data. This is clearly breaking essential
An earlier email in this thread reported that the recent changes also
break pywikibot, but maybe this was another part of the changes and the
one-week time-to-update I complain about does not apply there (maybe
this break was clear earlier so the team there had more time to adjust?).
You really need to give people more time to accommodate data model
changes -- and you should start counting the time when you have finished
and publicised the documentation of a change. I can't believe that my
question on the type IDs in JSON and RDF is still unanswered. I would
really like to release an update of our software and online tools next
week, so it would be good to know by then. Does nobody know this yet, or
do you not have enough resources to say it, or what is the problem? We
are no longer in those early years where everything was new and there
were no applications to break.
Faculty of Computer Science
Technische Universität Dresden
+49 351 463 38486