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36C3 Wikipaka WG: Live querying: let’s explore Wikidata together!

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    Music
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    Herald: We'll do some live querying with him
    so you were told to think of some ideas that
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    we could search for in Wikidata and when
    we get to that point I would ask you to
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    raise your hand and wait till I get to you
    with the microphone so that the people in
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    the stream can also hear what we're
    talking about so that's the thing I'll go
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    back to Lucas and we still have
    translations. Wenn ihr es auf deutsch hören wollt
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    wir haben immen noch Übersetzter, die alles versuchen
    es Euch nochmal auf Deutsch zu erzählen. Also hört mal rein.
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    Lucas: Does anyone have a query?
    Yes, in the front there. We have a question allready.
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    Audience member: Is it possible to find all circular family trees?
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    L: All circular what?
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    AM: Family trees
    L: It's certainly possible to find
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    some. Finding all it's probably going to
    be a timeout but there would be something
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    like select, probably child would be
    the simplest, so item child plus item
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    again. So if we put the star like earlier
    then you could then every Tree would
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    match that, but with the plus it means it
    has to be at least one child link or more,
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    and let's just add a "limit 1" because I'm
    not that optimistic that this is even
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    going to find one, but I'm pretty sure we
    cannot find all of them, but let's see if
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    we can find one and this might just take a
    while, but I don't think there is a good
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    way to do this otherwise unless you
    download one of the dumps either the JSON
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    data dumps or the RDF dumps which is the
    same data format used here and then you
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    can do it locally without an timeout.
    I don't think there's much I can optimize
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    about this query is pretty short unless
    like I had an idea that people named John
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    are more likely to have these kinds of
    cycles, then we could filter it down first
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    but you men. I'm afraid that is not going
    to work it looks like. Yes, timeout. And
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    you can see the thing is written in Java
    the server dragazines. One thing we
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    can do with this "P40+" is something like
    search start with a certain mythical
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    creature such as King Arthur. I hope I can
    find him like this. Search is being alright
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    3d map of EDT. There we go, that's the
    legendary British or Welsh king and then
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    we are searching for an item who is
    definitely a real human and who has a date
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    of birth and we say the date of birth
    should be greater than at say 1950 and
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    this is a date time value and this let's
    even say 1980. I think that might be
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    No more efficient. There we go. No
    results, okay. I thought King Arthur had
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    some real descendants. Though then it was
    some other mythical creatures. Let's just
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    start with any ancestor who has the item
    as child and the ancestor is also instance
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    of mythical creature, mythical character.
    Let's see if we have any mythical
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    characters with children who are born
    after 1950. Oh I still have the "limit 1"
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    here could make that a "limit 10" probably
    or something, but I'm optimistic I think
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    there are some people here, especially, I
    think, even British MPs, there's some
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    that's already on the list of example
    queries British MPs with mythical
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    ancestors and there's lovely have traced
    their lineage back to some 6th or 5th
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    century person and you have all the
    apparent links in there and then it's kind
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    of tricky to figure out where it starts
    being wrong. Oh that's not working out so
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    well. Does anyone else have ideas in the
    meantime? There, way in the back.
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    Someone: Thank you
    Audience member: We all know that stupid
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    game in Wikipedia where you try to find
    the Adolf Hitler page by only clicking
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    links, so can you find the number of pages
    that are directly connected to the Adolf
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    Hitler page in Wikipedia?
    L: You can. Oh that was a timeout, dammit.
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    So that would be kind of ... It's a one funny
    story about that for example is there's
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    the first example we
    have here is cats and why do we have cats
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    and not dogs? Because if you search for
    dogs the second result, no, it's the
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    fourth result by now, but that's the
    thought of Hitler and we don't really want
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    that and normally so we usually use cats
    as the example instead but let's just
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    search for anything where the item has any
    connection and we don't care which
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    property it is to Adolf Hitler, like that,
    and we are going to find 920 results. ok
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    some of these are site links so we also
    want the item to have some label which
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    uses this new namespace and we want only
    the English label so the language of the
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    label should be in English and we then we
    just select the item and the label and
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    hopefully that's still pretty efficient.
    Here we go NSDAP membership number
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    that's actually a property but I assume it
    has as the example yep there's a property
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    example here as NSDAP number 1. World War
    two has probably of cause of death do we
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    have him as an example on cause of death
    really? and we have nitric acid poisoning,
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    stroke, cholera, shot to the head, cyanide
    poisoning, hanging, That's a very pleasant
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    list. Do we need to have that many
    projects handfuls of closet yeah then we
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    have Nazi Party, Klara Hitler, I don't
    know who that is, 1936 Summer Olympics,
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    all kinds of things, so that's how
    you can find all the things with a direct
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    connection to Hitler. Any other
    examples? Yes, over there in the right, or
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    was there already somewhere someone back
    there that I missed
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    AM: Can you find the
    cheapest public infrastructure projects in
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    Germany?
    L: The cheapest public infrastructure
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    what?
    AM: Projects
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    L: Projects
    AM: Like a bridge building
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    L: I don't think we're going to have a
    full dataset about that but you can try.
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    Let's start with a more expensive one and
    [crackling noise]
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    L: see - perhaps move away from the box,
    that might help. Let's start with a very
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    expensive project and see just what the
    data model looks like so what does
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    infrastructure project look like what's
    what was the cost so the cost is probably
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    going to be in euro and I don't know how
    to write here over there okay it's a
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    property called cost in Euro and does it
    have something like instance of
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    international airport, building under
    construction, Greenfield Airport, proposed
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    airport being built, so we could check
    first is Berlin Brandenburg Airport, is
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    that an instance of some subclass of
    public infrastructure? Is that a thing?
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    that looks like the wrong item what is
    this this is nothing. Okay. There's anything
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    linked to this item? no nothing like
    suicide. Okay. So it could be an
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    international airport is a subclass of
    airport which is a subclass of an
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    aerodrome which is an architectural
    structure, and we can search for
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    architectural structures, so the structure
    would be an instance of subclass of
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    architectural structure, and it would have
    a cost, and order by the singing costs I
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    think it's 10 and we're probably going to
    get things in like yen or some other
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    currency where this number is just going
    to be very high because we're not taking
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    any conversions into account right now but
    let's see if we find something there. What
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    is it doing? Okay... not sure why this is
    taking so long. Let's try a second version
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    in the mean time where we quantity amount
    is cost and various quantities units
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    should be the euro they're still running
    and yeah let's try this that works any
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    better or not? Okay, this was a timeout. This
    looks like it's going to be a timeout as
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    well. I don't know, we can just search for
    the most expensive things at all. Remove
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    this part, there we go. This costs 55
    billion euros. What is this thing? Power
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    of Siberia, natural gas pipeline. That's,
    that's in euro, the costs? Apparently. And
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    then this is 15 billion euros and then
    8.77 find something that's the channel, oh
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    the Channel Tunnel is expensive. The
    Brenner Tunnel was also expensive.
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    laughter
    And Stuttgart 21 took about 21 whatever
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    was also- or is projected to be expensive.
    Do we have one cost or several? Okay in
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    2018 we have a cost of 7 billion. Yeah, so
    let's sort by the ascending constant set
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    because that was what we actually wanted
    and then we get... okay now we're going to
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    get a lot of things that aren't really
    infrastructure projects we have the whole
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    and a hot and energetic universe. Does
    that mean it's a no budget film or what?
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    Okay. So we would need some kind of ...
    Let's say, let's do duck typing instead of
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    saying it is an infrastructure project,
    let's say it has, I don't know, a
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    coordinate location. And if it has a
    coordinate location, we're going to call
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    it some kind of infrastructure project, or
    at least it's not going to be a
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    documentary film. Perhaps that works
    better. Yeah, so 21,000 euros cost this
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    thing which was in France. Oh, okay,
    right, it should also be country Germany.
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    Here we go. That's 400,000 euros for
    fountain in Stuttgart. Does that count? I
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    guess. And that's the engines of something
    it doesn't even have a German la- an
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    English label, just a German one. Wait...
    Oh, so this is the class of all the
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    fountains with exactly this name which are
    a subclass of well and are all named after
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    this goddess, okay, cool. Yeah so then we
    have some of these cheap projects, which
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    is… this public square… a bridge – oh
    yeah, there's this tiny bridge, a
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    footbridge, has even an image, that's what
    it looks like, and it costs, what was it,
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    1.6 million euros already. Wow. And then
    we have another public square. Yeah. So,
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    "cheap public infrastructure projects".
    And also probably "infrastructure" in
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    quotes, because we're really just saying
    it has a location and "Country: Germany".
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    And, yeah, I can send this query around
    afterwards. And this didn't work, this
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    didn't work. Okay, any other ideas? That's
    bad news. We could try to continue with
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    some of these. Was there something? Oh,
    from the Camera Angel!
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    AM: I have a question! I saw that with
    Wikidata Query Service we can draw these
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    nice trees and have images in them, and
    one example that came to my mind was all
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    the programming patterns – programming
    design patterns, but grouped by their
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    kind, like they're structural patterns,
    convenience patterns, and so on, and like,
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    can we draw a graph and maybe put an image
    in them.
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    L: We can try that. So let's see how
    that's modeled, I don't know, with the
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    visitor pattern for example. That's a
    design pattern what kind of statements
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    does have. It's a subclass of behavioral
    pattern, is this a programming thing or
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    already…? Oh yeah it's a soft… okay it's a
    software design pattern. So we should say ...
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    We're going to have a pattern with
    its label and a pattern kind with its
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    label and the pattern is going to be a
    subclass of the pattern kinds, which is
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    going to be some subclass of – what was
    it? Of software design pattern – and I'm
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    just going to copy this ID so it's the
    right one – label service, and say, I
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    would like to see this by default in the
    graph view. Here we go. Well that looks
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    not as bad as I thought. We have a lot of
    structural patterns, behavioral patterns,
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    one architectural pattern, a few
    creational patterns, and one fundamental
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    pattern. Yeah. And… yeah what we could
    also do is, if we do this, then we should
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    also see connections of all of these.
    Now we have the tree rooted at
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    software design patterns, we have monads,
    and fundamental pattern is a kind of
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    software design pattern. Structural
    pattern… and it's all linked there and
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    this is working… very well, I… That's much
    better than I expected. I expected a huge
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    mess of… because it sometimes gets
    different to determine when should you use
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    "instance of" and when should use
    "subclass off", like if it's software or
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    patterns like this, I expected we would
    have to account for both of these, but
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    this looks very good to me. I think we
    don't need to do anything with this query.
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    Yeah, so that is, uhm, software design
    patterns by a pattern tree.
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    Okay. Any other ideas? Or I can try to
    keep optimizing this one
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    AM: Which cities have applied to be host
    city of the Eurovision Song Contest the
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    most times but were never successful?
    L: Oh!
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    Laughter from Audience
    L: That's a very good question. I don't
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    know if we have– do you know who applied
    for this year or for some year? But I
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    could check if the state if that's modeled
    anywhere. Uhm, I need some example cities
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    so… let's check ESC 2018 if it has
    information on where it took place, which
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    one won the bid, but also who was
    nominated or something, or who applied… We
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    have "presenters", we have "followed by ",
    "start time", "end time", "participants",
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    we have the winner, do we have a location
    at all? Oh yeah, there it is. Okay, we
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    have a country, and a location, but I'm
    not seeing any other countries here, and I
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    assume that information is not going to be
    on the country item. It's possible that we
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    have some separate item for "Eurovision
    2018 Bid" or… Well wait, it would have to
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    be "which city", because the country is
    determined by the winner isn't it? So the
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    city, but I suspect we don't have that
    information. We have a list of host
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    cities, but that's just… a Wikipedia list
    article.
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    Interference noise
    Do we have to switch to the other mic? Oh
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    no, that sounds great! Okay. Yeah, so we
    don't have any of the structured
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    information here. It's just linking all of
    these Wikipedia articles together, and
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    then here is the actual list with the
    different venues. But I don't think we
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    have that information in Wikidata at the
    moment. We could add it, you'd have to
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    figure out the data model, but it would
    probably be relevant enough, I think.
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    I wonder if we have that for the Olympic
    Games. So, Olympics 2020, do we have the
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    process of who applied to host those? Uhm.
    We have a location. We have parts. Let's
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    check. Perhaps English Wikipedia has a
    separate article about the selection
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    process for the 2020 Summer Olympics.
    Doesn't look like it. "Host city
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    selection". No I don't see a main… oh no,
    there! "Bids for the 2020 Summer
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    Olympics", that's the Wikipedia article.
    Does that have any useful information on
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    Wikidata? Bids for Olympic Games no.
    Damnit. So you can see, when these bids
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    all happened, but we don't have the
    bidding countries and cities apparently on
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    Wikidata, at least not as far as I can
    see. Bids for the… 2012 for example…
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    No, sadly, we don't have that information
    yet. Did this one run by way? No.
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    Any other questions?
    Herald: Our translation angels had a question.
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    H: They want to know, if can give them the
    countries with the most colorful flags
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    L: Yes! That [interference noise] should
    be possible. So "select country", and the
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    "count of the colors as counts"
    [interference noise] the country has,
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    oops, has a flag, not the "flag image", a
    flag, and the flag has color. And it
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    should be "color" and not "colors", and
    then we group by country so this is a bit
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    like a [noise] grouping and aggregate
    functions
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    [Interference noise]
    Interferene noise*
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    Do we need to use the other microphone?
    [Noise] Okay [Noise] But then you can't
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    really walk around anymore.
    H: Hello hello? Hello hello? Muss man da
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    noch was machen?
    L: Okay so now… This could be really fun!
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    Yeah, so we are searching for countries
    with flags, and hope that the flags have
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    colors and been counting them, and what I
    didn't do is… what's this? Do I want to
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    know? Okay, okay it's at least it's not
    the straight pride flag, I guess. Does
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    this have 14 colors? No, what was it? No,
    eight, I guess, one, two, three, four,
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    five, six, seven, eight, yeah. That's
    accurate. Yeah, I didn't filter for
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    countries here, the thing is, country is
    really a stupidly complicated term, so
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    what I did was… queries… I have a pre-
    prepared query for the UN member states
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    somewhere, which I just copy all the time.
    And this is now going to be called a
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    state, and then we only get state flags,
    uhm, and there's exactly– oh, right. I
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    need to group by "state" and "state label"
    and copy these up here as well, and then
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    it will hopefully work, and we will find
    out that… the United Kingdom has… 12?
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    I suspect that's because it has four flags,
    which all have the same rank, or a no– no
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    it should be five, right? United Kingdom
    and Northern Ireland, Scotland, Wales and
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    England. Let's search for "flag". Flag is
    the flag of the United Kingdom, no? Why
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    does it have 12 colors? It has blue, red,
    white… wat. I see. But that still doesn't
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    explain the 12. Let's count only the
    distinct colours "distinct", there's auto-
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    completion, thank God, perhaps that helps
    . Though I don't know why it would have…
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    oh it would have had the state multiple
    times because it's a sovereign state
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    multiple times probably. Let's check. Yeah
    the United Kingdom is, it's a Commonwealth
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    realm, and an island nation, and a
    sovereign state, and that's probably why
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    we got it multiple times, and, yeah that
    looks more reasonable. South Africa,
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    Ecuador, South Sudan, and what we can also
    do is, add the, of the flag, the image and
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    call that I, because I can't be bothered
    to type the whole thing, and add that
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    here, and also add it to the "group by",
    because otherwise it's not the right
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    aggregate and I can't be bothered to write
    "sample" with one hand, and then we can
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    hopefully also see it. Oh, we get two
    images of the flag of South Africa. That
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    also looks like one of them should be
    "preferred rank", but anyways, we can
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    switch to image grid, and then we can see
    all these colorful flags. One, two, three,
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    four, five, six, yeah. That's six. And
    this is more than six, so I guess, I would
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    say that should actually be two separate
    items, for this old flag and– no, this old
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    flag and the new flag, but… This is six…
    is that only six colors? I'll believe it.
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    This is six colors, six, and then we have
    five colors, yeah. So here are the, let's
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    just add a comment there, and I will tweet
    this out later as well, "colorful state
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    flags". Yeah. And also we can use
    the image grid as the default view.
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    We probably have time for one more question,
    if it's a short one. Though I won't be
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    able to type very fast. Yes, let's
    hope this works. Otherwise I can repeat it
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    for the stream if I hear you.
    AM: So does it work? Yep seems so. I don't
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    know if it's possible, but the smallest
    images that are on Wikipedia? So, by image
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    size?
    L: That would not be possible with the
  • 28:02 - 28:09
    Query Service I think. But I think on
    Commons you can search… can you search?
  • 28:09 - 28:14
    Whoops, I don't have that search shortcut
    set up here. Can you search by image size?
  • 28:14 - 28:28
    I think that might be possible. Advanced
    search, file type, sorting order… No.
  • 28:28 - 28:34
    You could probably sort by a file size in an
    SQL query. Which is not a thing from the
  • 28:34 - 28:40
    Wikidata Query Service, but it's possible
    with something else and as it happens I am
  • 28:40 - 28:44
    going to have another talk later, where I
    talk, about among other things, how you
  • 28:44 - 28:48
    can write SQL queries against the
    Wikipedia databases, and then we might be
  • 28:48 - 28:53
    able to find a solution for that, and
    that's I think at 6 p.m. today over in the
  • 28:53 - 29:06
    Esszimmer, or you come over to me after
    the talk and then I can try to figure it out there.
  • 29:06 - 29:10
    H: A last emergency idea that we have to
    try out?
  • 29:10 - 29:16
    H: I'm muted. Do you have ano– one more
    idea? A small idea maybe we could do but
  • 29:16 - 29:18
    other than that I think we are, so– filled
    the time quite well.
  • 29:18 - 29:23
    L: Yeah I think we're done. But if you
    have any other ideas, you can always
  • 29:23 - 29:30
    contact me on Twitter @wikidatafacts, or
    on Mastodon as well, and then I will see
  • 29:30 - 29:39
    what I can do for you. Yeah. Thanks.
    H: Thank you very much, Lucas, that was a
  • 29:39 - 29:42
    great introduction to Wikidata querying!
  • 29:42 - 29:44
    Music
  • 29:44 - 30:10
    Subtitles created by c3subtitles.de
    in the year 2021. Join, and help us!
Title:
36C3 Wikipaka WG: Live querying: let’s explore Wikidata together!
Description:

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Video Language:
English
Duration:
30:10

English subtitles

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