[Qgis-developer] Questions/Suggestion on virtual layers

[Yves Jacolin]

Andreas,

In the layer toolbar, after the "Add a delimited text Layer" icon you have the 
"Add a virtual layer" tools. In the panel you can choose a virtual layer name.

If you create two virtual layer, when you come back to this windows, the 
dropdown list will show you the two layers that you can edit.

But you are right, if there is an error, the virtual layer won't be saved.

Y.
On Wednesday, March 02, 2016 17:04:15 Neumann, Andreas wrote:
> Hi Yves,
> 
> Thanks for your reply. What drop down list are you talking about? In
> what menu/dialogue/context menu?
> 
> Andreas
> 
> On 2016-03-02 16:39, Yves Jacolin wrote:
> > Andreas,
> > 
> > I though that you can edit the request of your virtual layer. In the drop
> > down list you c an choose the one to change.
> > 
> > Am I wrong?
> > 
> > Y.
> > 
> > On Wednesday, March 02, 2016 16:27:07 Neumann, Andreas wrote:
> >> Hi,
> >> 
> >> I am experimenting with the virtual layers. They are quite cool!
> >> 
> >> I have some suggesions/questions:
> >> 
> >> * It would be nice to have a preview of my query results. Currently it
> >> is either it works - or not. If it works, but the results are wrong you
> >> have to start from scratch. I would suggest that when you press on the
> >> test button you would not only display "No error" or the error message,
> >> but maybe the first 10 rows of the result.
> >> * Updating the virtual layer: it would be really nice if I could
> >> edit/improve on my virtual layers without having to start completely
> >> from scratch. --> Oh - now I found out that if you select an existing
> >> virtual layer and then use "Layer" --> "Add Layer" --> "Add Virtual
> >> Layer", that you can refresh an existing virtual layer. This is really
> >> not obvious. I think this is more a usability issue.
> >> * it is not very obvious how you can reuse an already existing
> >> geometry column. I discovered it by accident, that you can use
> >> layer.geometry (regardless of the original name of the geometry column),
> >> but I think that it is not obvious. A better hint in the the tooltip
> >> would probably help.
> >> * Unique identifier column: If you join several tables, you often have
> >> the issue that you need to create an artificial primary key. Could we
> >> offer a preconfigured builtin pkey - something like a rowid  for such
> >> cases?
> >> * What is the exact purpose of the "Embedded Layers" where you can
> >> add/import/remove layers? I noticed that existing layers of the project
> >> work anyway without adding/importing them first. Is the idea that you
> >> can work on layers that aren't in the project?
> >> 
> >> Should I open feature request tickets for these or are there already
> >> plans to address one or the other of the above issues?
> >> 
> >> Thanks anyway for this interesting new feature!
> >> 
> >> Andreas