[Qgis-developer] Sample

Jürgen E. Fischer jef at norbit.de
Tue Jul 15 00:22:59 PDT 2014

Hi Paolo,

On Tue, 15. Jul 2014 at 08:50:10 +0200, Paolo Cavallini wrote:
> > Yeah I'm thinking it might just be slow for something like shapefile where is there
> > no index on that column and it has to get each value to find the unique ones.  I'm
> > not looking at the code, just guessing.
> Thanks for your comments.
> I found it rather slow for large PostGIS tables.

As slow as

SELECT DISTINCT attribute FROM table ORDER BY attribute LIMIT 10



Jürgen E. Fischer           norBIT GmbH             Tel. +49-4931-918175-31
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QGIS release manager (PSC)  Germany                    IRC: jef on FreeNode                         

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