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missing a Statistical Unit type in the datamodel

Recently Statistics Netherlands has published a INSPIRE harmonised Statistical Units WMS and WFS:

They can be reached via:

http://geodata.nationaalgeoregister.nl/su-vector/wms?
and
http://geodata.nationaalgeoregister.nl/su-vector/wfs?

The biggest problem we encountered for creating the harmonized service, was that we could only add one layer with one feature type in the service. In the original service we had one layer for each different SU, but now we had to put them all together. This is not very useful for the users, because they have to use a filter to get them separated again. We added the fields theme and year to be able to filter the separate SU's out again. Luckily, the validator accepted this. You now have to use an SQL query in QGIS to separate the different types again like I show in the picture below:

 

We also used the tessellation attribute to store the SU type and year. It is shown with the example below;

http://geodata.nationaalgeoregister.nl/su-vector/wfs?request=GetFeature&version=2.0.0&typeNames=su-vector:AreaStatisticalUnit&filter=%3CFilter+xmlns=%22http://www.opengis.net/ogc%22%3E%3CPropertyIsEqualTo%3E%3CPropertyName%3Esu-vector%3Atesselation%2Fsu-vector%3AStatisticalTessellation%2Fsu-vector%3AinspireId%2Fbase33%3AIdentifier%2Fbase33%3AlocalId%3C/PropertyName%3E%3CLiteral%3Eprovincie.2014%3C/Literal%3E%3C/PropertyIsEqualTo%3E%3C/Filter%3E

I'm curious to know how others solved this problem.

Best regards,

Pieter Bresters

  • Francisco CALDEIRA

    By Francisco CALDEIRA

    Hi Kathi and Pieter,

    Kathi I have an Access Denied, on Chrome, Firefox and IE in my office but at home :-) I can see your page.We have a very restrictive infrastructure overhere.   

     

    About the WFS I can see some layer but not all.

     

     

     

    Regards

    F

     

     

     

     

     

  • James PASSMORE

    By James PASSMORE

    Anyway I implemented more than one harmonized layer (all polygons) in one service with GeoServer (WMS).

    For instance data of the theme Human Health and Safety

    http://inspire.ine.pt/geoserver/COD2014_PT_CONTINENTAL/wms?REQUEST=GetCapabilities&SERVICE=WMS

     

    As I understand it this view service doesn't follow the Data Specification on Human Health and
    Safety, which states that (section 11.1 Layers to be provided by INSPIRE view services) you must supply a layer called (name) HH.HealthStatisticalData with a title Health statistical data .  Instead you have layers with names HH.HealthStatisticalData_01 and HH.HealthStatisticalData_02.

    To get around this restriction you can provide a group or root layer (HH.HealthStatisticalData)

     

     

     

     

  • Bresters PIETER

    By Bresters PIETER

    Hello James,

    Thank you for your tip on using group layers for the multi layer problem. I have discussed this with our hosting organisation PDOK. Their reply was that using grouplayers is not accepted by the WMS validator, because it needs a default style and you can't attach a style to a grouplayer.

    Best regards,

    Pieter Bresters

     

  • James PASSMORE

    By James PASSMORE

    Hello Pieter,

    you can't attach a style to a grouplayer.

    Obviously that statement is demonstratably wrong, I mean when you request a layer from a WMS whether it be a group layer or not, you get a map, so a default style MUST have been applied.

    Here's a related posting:

    https://themes.jrc.ec.europa.eu/discussion/view/13952/layer-naming

     

    James

     

     

     

     

  • Bresters PIETER

    By Bresters PIETER

    Hello James,

    My service provider PDOK in the Netherlands told me it was not possible to attach a (default) style to a group layer in the Geoserver version they use. The WMS validator requires this according to them. There is also a problem with required keywords for group layers.

    If you say it is possible, Can you explain how to do this in Geoserver? 

    Could it be a Geoserver version problem?

    Pieter

  • James PASSMORE

    By James PASSMORE

    Hello Pieter,

    Perhaps we are talking about different things when we talk about default styles; I mean the style that is applied by default, that is when no style is specified in a WMS GetMap request.

    To be able to get a map image from some vector data a style must be applied, that is a fact.  If a style isn't applied we don't get a map image, instead we get an exception,or perhaps a blank map, that's how a WMS works.

    So for example in the following GetMap request for a group layer provided by GeoServer

    http://ogc.bgs.ac.uk/digmap625k_gsml_insp_gs/ows?SERVICE=WMS&LAYERS=GE.GeologicUnit&TRANSPARENT=TRUE&VERSION=1.3.0&REQUEST=GetMap&STYLES=&EXCEPTIONS=INIMAGE&FORMAT=image/png&CRS=EPSG%3A4326&BBOX=56.46545854640886,-4.629763507503928,57.18751615063015,-4.064859617142562&WIDTH=665&HEIGHT=850

    We don't specify a style (STYLES=&)  but we get a map image, so a default style must have been applied.

    The default style that is applied is the combination of styles from the combined (or grouped) layers.  So the problem your provider is referring to is you cannot give a name to this default style, or change indeed change the styling in the group layer.

    For geology not only the technical guidance, but also the regulation, tells us what the layer name and title must be, but there are no musts for style name, so the group layer works for a  geology WMS to conform to the regulation. 

    I admit it isn't particularly useful if the members of your group layer are available at the same scales, for usefulness in such a situation you would need to access your layers by name and not at the group level.  If, on the other hand the members of your group layers are scale dependent, then such an approach would work well.

    If the regulation and not just the technical guidance says/implies that your INSPIRE portrayal service (WMS) must have the layer name HH.HealthStatisticalData, but you don't supply one then your service will not be compliant, the fact that you have a named default style will not help you, so you will need to find a pragmatic solution.

    Hope this clarifies

    James

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

Statistics & Health

Statistics & Health

Join this group if you would like to share knowledge or ask questions regarding the INSPIRE implementation of Statistical Units [SU], Population Distribution (Demography) [PD] or Human Health and Safety [HH] data themes