Hello David,

thanks for pointing out these faceting issues very clearly. At first glance I agree with all your points and the behaviour is awkward or simply buggy in some cases. We will need some time to investigate further.

Many thanks,
Markus

On 10 Feb 2017, at 22:24, Herbario SANT <sant.herbarium@gmail.com> wrote:

Hello.

I am trying to play with faceted results from the occurrence api, but returned values are very odd IMHO.  

Perhaps I am misunderstanding how faceting should work? Or there might be some problem with the indexing of these particular datasets.   
I am pretty lost.  This is what I found:


(1) RESULTS COUNT NOT MATCHING SUM OF ALL FACET COUNTS

I put a simple example so everything is returned in one page.

http://api.gbif.org/v1/occurrence/search?facet=ScientificName&limit=10&collectionCode=SANT-Lich&genusKey=2581943

The count value is 4, the number of results is 4.
But the number of facets is 1, and its count is 2.

The faceted term ScientificName is a mandatory field, so no null values should happen. I would expect every occurrence having a value for it.
And the number of values is short, so everything is returned in one request (no paging needed).
So, in such a case shouldn't the sum of facet counts be equal to the number of results?
Why the count of the faceted name is not 4?


(2) LOWERCASE FACETS (facets values not matching results values):

Look at the same api request above (plant names)
 
results:
Scientificname: "Generic_name specific_name (Basionym_Authors) Name_Authors"

facets:
name: "generic_name specific_name (basionym_authors) name_authors"

Why are the facets names always in lowercase?
I would say that is an error which shouldn't happen.

But I reported it some days ago and got no answer, so I wonder if this is the intended api behaviour.

http://dev.gbif.org/issues/browse/PF-2758

Not only scientific names are lowercased. This also happens to collectionCode in the next question.


(3) FACETING COLLECTIONCODE VALUES of a single institution fails depending on filtering parameter used to match the institution (code or uuid):

Our institution (uuid= def87a70-0837-11d9-acb2-b8a03c50a862 , institutionCode=SANT) serves datasets from 4 collections, which should sum up more than 100000 records.

Why do I get only 2 of our 4 datasets faceted in the following request, which uses our publishingOrg uuid? (uuid should be the preferred option to do this, as code might not be unique for our institution)

http://api.gbif.org/v1/occurrence/search?facet=collectionCode&limit=0&publishingOrg=def87a70-0837-11d9-acb2-b8a03c50a862

Why do I got 4 of 4 if I filter the request using institutionCode instead? (fortunately, nobody else uses the same institutionCode yet, so numbers are correct)

http://api.gbif.org/v1/occurrence/search?facet=collectionCode&limit=0&institutionCode=SANT

And why do counts differ for the same facet value (sant-lich) in those two requests?
(9960 in the 1st request, 10007 in the 2nd one)

Why are facet values lowercase again? ("sant-lich" instead of "SANT-Lich")


(4) FACETING SCIENTIFICNAME FAILS FOR SOME DATASETS, but works as expected for others:

More than 1000 faceted Scientificnames returned for our SANT-Lich and SANT-Algae collections. Both of them look correct results:

http://api.gbif.org/v1/occurrence/search?facet=ScientificName&limit=0&collectionCode=SANT-Lich&ScientificName.facetLimit=50000&ScientificName.facetOffset=0

http://api.gbif.org/v1/occurrence/search?facet=ScientificName&limit=0&collectionCode=SANT-Algae&ScientificName.facetLimit=50000&ScientificName.facetOffset=0

But no facets returned for SANT-Bryo (which contains several hundred distinct scientificname values):

http://api.gbif.org/v1/occurrence/search?facet=ScientificName&limit=0&collectionCode=SANT-Bryo&ScientificName.facetLimit=50000&ScientificName.facetOffset=0

And only 7 facets for SANT scientificnames (should be over 10 thousand, as this is by far our largest dataset):

http://api.gbif.org/v1/occurrence/search?facet=ScientificName&limit=0&collectionCode=SANT&ScientificName.facetLimit=50000&ScientificName.facetOffset=0



Other than the lowercase facets issue (2), I couldn't reproduce issues 1,3,4 in other institutions datasets. 
So I wonder if all this is somehow related to a wrong indexing of our IPT.

Has anyone else detected these problems?

Thanks a lot in advance for your help

David

-- 
David García San León
Herbario SANT
Universidade de Santiago de Compostela

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