[Qgis-developer] Filter on joined tables

[Martin Dobias]

Hi Hugo

On Fri, Feb 14, 2014 at 4:36 PM, Hugo Mercier <hugo.mercier at oslandia.com> wrote:
> Hi,
>
> We are asked to work on subset filtering when a qgis layer has joined
> fields.
>
> Currently, the filter feature has been disabled on a layer with joined
> fields to circumvent a bug (see http://hub.qgis.org/issues/3858 and
> http://hub.qgis.org/issues/3857).
>
> What if you want to implement filtering on a table with joined fields ?

I think there should be a switch in the GUI allowing the user to do
filtering with native query (if supported by provider) or with
QgsExpression (always supported, allows joined attributes in join).
For simple cases the QgsExpression filter could be even translated to
provider's native subset query for greater efficiency.

Regards
Martin