[QGIS-Developer] QGIS 3 > Processing: some test

Giovanni Manghi giovanni.manghi at gmail.com
Tue Jun 20 05:03:54 PDT 2017

Hi Nyall,

>> and dissolving by "distrito" the ogr2ogr based tool is 2/3 seconds
>> faster than the new native one.
> For comparison, how long did each take in total?

about ~28/29 seconds ogr and ~ 31/32 native (on a testing VM with
limited resources).

> Hmm - works fine here. Can you try turning off the invalid geometry
> checking in processing options? That's a little broken at the moment
> (with the error you've noted below)

if I turn off that option then it works, both dissolving by attribute
and a full dissolve.
The speed difference is not much (ogr always a bit faster in my
testing environment).

> Outdated message ;) It's refering to the option in processing settings.

yes, i realized it later.

> That should be really straightforward to add to the feature iterators
> now. But alternatively there's a processing alg which repairs
> geometries too (not in master yet, but in earlier 3.0 builds).

both very good news! but don't forget that in the economy of a work
day of a person that do all day this kind of operations, having an
option to fix geometries on the fly while clipping/intersecting/etc is
very important and save a lot of time. Of course having the same
functionality as separate tool is as much as important.


-- g --

More information about the QGIS-Developer mailing list