[Qgis-user] QGIS MBTiles

[Even Rouault]

Stefan

> 
> when I try to add a raster layer based on a local MBTiles file in QGis
> 2.14 I get this error:
> "Nicht unterstütztes Datenformat: D:\Files\Testdata.mbtiles ist keine
> unterstützte Rasterdatenquelle Cannot find min and max tile numbers"
> 
> Did someone successfully use MBTiles with QGis?

Yes sure.

This error messages comes from the underlying GDAL MBTiles driver. There is something in 
your dataset that it doesn't like. Either the driver isn't robust to this case, either the mbtiles 
isn't conformant. But hard to tell without access to the file. 

> 
> Where is QGIS searching for the "min and max tile numbers"? Does it have
> to be in one of the metadata tables?
> Or is it somehow calcluated on the fly?

It looks at the metadata table for 'minzoom' and 'maxzoom' entries. If not found, it then 
looks at the tiles table to query the min and max values of zoom_level.
The error could occur if the MBTiles dataset is completely empty. Otherwise I'm not sure 
without inspecting it.

Even

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Spatialys - Geospatial professional services
http://www.spatialys.com
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