Hi Hugo,
On 2016-03-02 17:17, Hugo Mercier wrote:
Hi Andreas,
On 02/03/2016 16:27, Neumann, Andreas wrote:
Hi,
I am experimenting with the virtual layers. They are quite cool!
I have some suggesions/questions:
1. 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.
True.
Note that you can also create a virtual layer using the DB Manager where
it can display the first rows of a query, as it is the case for other
databases.
I am not sure to love having these two very close but slightly different
dialogs. If anyone has a better idea in terms of usability, do not
hesitate to propose :)
Can one create new virtual layers in the DB manager? I know that I can
do queries on existing layers and load it as a new layer - but is this
the same thing like a virtual layer?
2. 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.
Yes ... I am more used to click on the addition icon, which makes it
more direct, but you are right, this is not perfect.
ah ok - the button works as "edit" if you have the layer selected. Maybe
then we should rename the tooltip from "Add Virtual Layer" to "Add or
Edit Virtual Layer"
An entry in the right-click menu ?
Yes - that was my first idea - to look for an entry in the layer context
menu. Of course this entry should only be there if it is a virtual
layer.
Edit - you can also use the drop down menu of the creation dialog to
switch between different virtual layer definitions, as mentioned by Yves
yes - now I found it - thanks!
3. 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.
Indeed it appears to be not documented.
This would just require an additional sentence in the tooltip of the
Query panel, after the sentence "Any functions from SQLite or Spatialite
can then be used in the query.:
To add or access existing geometries of a table, you can use
"tablename.geometry", regardless of original geometry column's name.
4. 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?
Good point. An autoincremented id is already generated on the feature.
That may not be a problem to add a "rowid" column in that case.
That would be cool to have.
5. 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?
Yes it is.
You can for example embed layers from the project, save the virtual
layer to a QLR and reload it in a new project, the referenced layers
would not need to be already loaded.
There may be some documentation needed as well here.
Maybe we could add another tooltip here, explaining that one can add
layers that are not in the project - and that you need to "embed
existing layers", if you want to save to a qlr and load it in a
different project.
Should I open feature request tickets for these or are there already
plans to address one or the other of the above issues?
Unfortunately, no plan yet.
Thanks for your tests and feedback !
Ok - I will open feature requests for the above, where useful.
Thanks,
Andreas
__________ Information from ESET Mail Security, version of virus signature
database 13116 (20160302) __________
The message was checked by ESET Mail Security.
http://www.eset.com
Hi Hugo,
On 2016-03-02 17:17, Hugo Mercier wrote:
Hi Andreas,
On 02/03/2016 16:27, Neumann, Andreas wrote:
Hi,
I am experimenting with the virtual layers. They are quite cool!
I have some suggesions/questions:
1. 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.
True.
Note that you can also create a virtual layer using the DB Manager where
it can display the first rows of a query, as it is the case for other
databases.
I am not sure to love having these two very close but slightly different
dialogs. If anyone has a better idea in terms of usability, do not
hesitate to propose :)
Can one create new virtual layers in the DB manager? I know that I can
do queries on existing layers and load it as a new layer - but is this
the same thing like a virtual layer?
2. 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.
Yes ... I am more used to click on the addition icon, which makes it
more direct, but you are right, this is not perfect.
ah ok - the button works as "edit" if you have the layer selected. Maybe
then we should rename the tooltip from "Add Virtual Layer" to "Add or
Edit Virtual Layer"
An entry in the right-click menu ?
Yes - that was my first idea - to look for an entry in the layer context
menu. Of course this entry should only be there if it is a virtual layer.
Edit - you can also use the drop down menu of the creation dialog to
switch between different virtual layer definitions, as mentioned by Yves
yes - now I found it - thanks!
3. 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.
Indeed it appears to be not documented.
This would just require an additional sentence in the tooltip of the
Query panel, after the sentence "Any functions from SQLite or Spatialite
can then be used in the query.:
To add or access existing geometries of a table, you can use
"tablename.geometry", regardless of original geometry column's name.
4. 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?
Good point. An autoincremented id is already generated on the feature.
That may not be a problem to add a "rowid" column in that case.
That would be cool to have.
5. 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?
Yes it is.
You can for example embed layers from the project, save the virtual
layer to a QLR and reload it in a new project, the referenced layers
would not need to be already loaded.
There may be some documentation needed as well here.
Maybe we could add another tooltip here, explaining that one can add
layers that are not in the project - and that you need to "embed
existing layers", if you want to save to a qlr and load it in a
different project.
Should I open feature request tickets for these or are there already
plans to address one or the other of the above issues?
Unfortunately, no plan yet.
Thanks for your tests and feedback !
Ok - I will open feature requests for the above, where useful.
Thanks,
Andreas
__________ Information from ESET Mail Security, version of virus
signature database 13116 (20160302) __________
The message was checked by ESET Mail Security.
http://www.eset.com
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