Hi Enrico, Hmm I didn't think of that, thanks for the idea ! But I can't use it since I may have several user at once.
Best, Olivier 2015-06-17 16:03 GMT+02:00 enricofer <enrico...@gmail.com>: > Hi Olivier, > In your case, I think that the best way to do this is to create a view > from the sql query and load it as layer, than, when qslider changes, change > the view definition with "ALTER VIEW" and reload the layer. > > Regards, > > Enrico Ferreguti > > Il giorno 17/giu/2015, alle ore 14:29, olivier [via OSGeo.org] <[hidden > email] <http:///user/SendEmail.jtp?type=node&node=5211452&i=0>> ha > scritto: > > Hi ! > > Is it possible to change the query of a postgis query layer in python > without reloading the project ? > > The goal is to have a parameter in my query that I'd be able to change > with a slider. > > I tried the QgsVectorLayer.setDataSource() method, but it makes QGis crash. > I tried the workaround described here ( > http://gis.stackexchange.com/questions/62610/changing-data-source-of-layer-in-qgis > ), writing and reading the XML file, but it also makes QGis crash. > > If not possible, is there a serious limitation behind this, or is the > feature just missing/bugged ? > > Example : > > I have this query loaded as a layer: > > "SELECT id, name, ST_Buffer(geom,25) as geom FROM my_table" > > But I want to be able to change the hardcoded buffer from 25 to some value > from a QSlider. > > Thanks! > > Olivier > > _______________________________________________ > Qgis-developer mailing list > [hidden email] <http:///user/SendEmail.jtp?type=node&node=5211424&i=0> > http://lists.osgeo.org/mailman/listinfo/qgis-developer > > ------------------------------ > If you reply to this email, your message will be added to the discussion > below: > > http://osgeo-org.1560.x6.nabble.com/Change-the-query-of-a-query-layer-postgis-tp5211424.html > To unsubscribe from Quantum GIS - Developer, click here. > NAML > <http://osgeo-org.1560.x6.nabble.com/template/NamlServlet.jtp?macro=macro_viewer&id=instant_html%21nabble%3Aemail.naml&base=nabble.naml.namespaces.BasicNamespace-nabble.view.web.template.NabbleNamespace-nabble.view.web.template.NodeNamespace&breadcrumbs=notify_subscribers%21nabble%3Aemail.naml-instant_emails%21nabble%3Aemail.naml-send_instant_email%21nabble%3Aemail.naml> > > > ------------------------------ > View this message in context: Re: Change the query of a query layer > (postgis) > <http://osgeo-org.1560.x6.nabble.com/Change-the-query-of-a-query-layer-postgis-tp5211424p5211452.html> > Sent from the Quantum GIS - Developer mailing list archive > <http://osgeo-org.1560.x6.nabble.com/Quantum-GIS-Developer-f4099106.html> > at Nabble.com. > > _______________________________________________ > Qgis-developer mailing list > Qgis-developer@lists.osgeo.org > http://lists.osgeo.org/mailman/listinfo/qgis-developer >
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