Re: [Qgis-developer] qgis2threejs issue

2014-10-28 Thread Minoru Akagi
Hi Paolo,

2014-10-28 3:45 GMT+09:00 Paolo Cavallini cavall...@faunalia.it:
 -BEGIN PGP SIGNED MESSAGE-
 Hash: SHA1

 Il 27/10/2014 19:24, doktoreas ha scritto:

 you need to set control to OrbitControls.

 Oh, I see, thanks.
 Why it is not the default?

Since the last used control is saved, I did not consider it carefully.
Now it's ok to change the default controls to OrbitControls, which has
more functions (e.g. arrow-key control and auto-rotation) and is
probably suitable for flat earth.

Regards,
Minoru
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Re: [Qgis-developer] error when saving modified features via wfs-t/qgis server

2014-10-28 Thread Giovanni Manghi
 Message: 3
 Date: Mon, 27 Oct 2014 09:46:54 +0100
 From: Ren?-Luc Dhont rldh...@gmail.com
 To: qgis-developer@lists.osgeo.org
 Subject: Re: [Qgis-developer] error when saving modified features via
 wfs-t/qgis server
 Message-ID: 544e067e.9000...@gmail.com
 Content-Type: text/plain; charset=utf-8; format=flowed

 Hi Giovanni,

 If tinyows and QGIS-Server can't save feature through WFS-T, it's
 probably an issue in the QGIS WFS Client, isn't it ?

HI René-Luc, thanks for the answer.

The tiny-ows issue seems to be isolated to the server side (or how I
configured it), as I can't find a client that works.

On the other hand I think there is an issue with qgis-server: qgis as
client can edit/modify with no issues certain features (ex: polygons)
published on geoserver, but the same features published with qgis
server return the error I posted in my first message. If the feature
is generalized, at some point the error when saving does not show
anymore.



cheers

-- Giovanni --
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Re: [Qgis-developer] QEP/RFC sqlite virtual tables

2014-10-28 Thread Matthias Kuhn

Hi Hugo,

Sorry for my slow response, I was quite busy the last days.

I'll try to explain a bit more what I have in mind.

For example there is the new expression function getFeature() which is 
an ad-hoc replacement for a join. I have been told that the performance 
for rendering is not very good, I assume this is caused by a lot of 
requests performed in the background. It would be great to be able to 
join this on the server side.


I would be very happy to see more of this introduced. For example I 
could well imagine a new Expression (Syntax just made up, that can still 
be designed in a more appropriate way)


  avg( c.population ) { LEFT JOIN cities c ON c.country_code = 
$thistable.code }


This should then be locally evaluated (for shapefiles et al) but 
forwarded to the server for database services (postgres and the like).


Now, as we have different backends and their syntax does not always 
match (most do standard sql, but there are extensions, think of ST_* in 
postgis, SDO_* in oracle spatial etc, and there is no guarantee, that a 
dataprovider supports standard SQL) we need an abstraction layer and 
cannot just assume that every dataprovider will understand the same thing.


I am planning to implement this abstraction layer for ordinary 
expressions in the near future. And I would be very happy to see that 
there is a way to extend this with aggregate functions. This will all 
require a fallback level (if the server does not support a given 
functionality, for shapefiles, to be sure that the result is the very 
same regardless of server function implementation details...). We 
already have this for ordinary expressions as we can just use the 
QgsExpression implementation.


I can only repeat, that I will be more than happy to see this fallback 
level implemented by means of sqlite virtual tables. But in my humble 
opinion it would be very unfortunate if there would be no way to 
optimize this tomorrow or the day after tomorrow. That's why I am asking 
if sqlite developers are open to collaborate because if the will to 
collaborate there is missing we will end up having to reimplement this 
functionality.


I totally agree with your statement A general cross-database SQL 
optimizer would need lots of work (in QGIS and/or SQLite) and may come 
later (if really needed)., but would append and will require either a 
re-implementation in QGIS, ending up in duplicated functionality 
(that's what Régis was worried about in the original mail) or will need 
the possibility to get deeper access to sqlite's internal data 
structures or callbacks to optimize where required. This will require 
cooperation from SQLite developer's side or forking sqlite..


Best regards,
Matthias

 
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Re: [Qgis-developer] Delay 2.6 release?..

2014-10-28 Thread Sandro Santilli
On Sun, Oct 26, 2014 at 12:09:55PM +0100, Luca Manganelli wrote:
 On Sun, Oct 26, 2014 at 11:16 AM, Nathan Woodrow madman...@gmail.com
 wrote:
 
  I think it makes sense to keep up with the funded bug fixing if we have
  the money
 
 
 Maybe the QGIS testing funding would fix all these probelms? Now it's
 funded!
 http://blog.vitu.ch/10102014-1046/crowdfunding-initiative-automated-testing​

That project is about making current tests pass and keeping them passing
for the future. Very important, glad it made it !

It won't be matter of a few days, nor it will involve fixing bugs that do
not have a test. But if bugfixes funded for 2.6 will come with a testcase
guarding for them not to come back again it'll be great.

--strk;

  ()   Free GIS  Flash consultant/developer
  /\   http://strk.keybit.net/services.html
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Re: [Qgis-developer] Delay 2.6 release?..

2014-10-28 Thread Matthias Kuhn

On 10/28/2014 10:50 AM, Sandro Santilli wrote:

On Sun, Oct 26, 2014 at 12:09:55PM +0100, Luca Manganelli wrote:

On Sun, Oct 26, 2014 at 11:16 AM, Nathan Woodrow madman...@gmail.com
wrote:


I think it makes sense to keep up with the funded bug fixing if we have
the money


Maybe the QGIS testing funding would fix all these probelms? Now it's
funded!
http://blog.vitu.ch/10102014-1046/crowdfunding-initiative-automated-testing​

That project is about making current tests pass and keeping them passing
for the future. Very important, glad it made it !

It won't be matter of a few days, nor it will involve fixing bugs that do
not have a test. But if bugfixes funded for 2.6 will come with a testcase
guarding for them not to come back again it'll be great.




Thank you for the clarification Sandro, this mail has escaped my notice.
I am also glad that this campaign made it. I will make sure that I will 
work on this in the upcoming weeks (not only) to ensure that new test 
cases being written now are taken into consideration.


-- Matthias

 
--


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http://blog.vitu.ch/10102014-1046/crowdfunding-initiative-automated-testing

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[Qgis-developer] PyQGIS standalone without x server

2014-10-28 Thread Ziegler Stefan
Hi 

Since I do not have access to a server w/o x server I cannot test it by myself. 
Does anybody know if a running x server is required to run pyqgis standalone 
apps? E.g. something like this:

app = QApplication(sys.argv)
QgsApplication.setPrefixPath(/home/stefan/Apps/qgis_master, True)
QgsApplication.initQgis()

QgsProject.instance().setFileName(os.path.join(current_dir,  bpav5000sw.qgs))
QgsProject.instance().read():

QgsApplication.exitQgis()

Best regards
Stefan 


Freundliche Grüsse 
Stefan Ziegler 
Kantonsgeometer 

Amt für Geoinformation
Amtliche Vermessung 
Rötistrasse 4 
4500 Solothurn 

Telefon +41 32 627 75 96
Telefax +41 32 627 75 98 
stefan.zieg...@bd.so.ch
http://www.so.ch 

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Re: [Qgis-developer] PyQGIS standalone without x server

2014-10-28 Thread Alessandro Pasotti
2014-10-28 11:47 GMT+01:00 Ziegler Stefan stefan.zieg...@bd.so.ch:
 Hi

 Since I do not have access to a server w/o x server I cannot test it by 
 myself. Does anybody know if a running x server is required to run pyqgis 
 standalone apps? E.g. something like this:

 app = QApplication(sys.argv)
 QgsApplication.setPrefixPath(/home/stefan/Apps/qgis_master, True)
 QgsApplication.initQgis()

 QgsProject.instance().setFileName(os.path.join(current_dir,  
 bpav5000sw.qgs))
 QgsProject.instance().read():

 QgsApplication.exitQgis()

 Best regards
 Stefan



I'm not sure if an X server is *always* required, what I know for sure
is that if you are going to use any SVG symbol or HTML formatted text
in a widget, then your script will crash with an ugly segfault if X
(or fake X) is not running.

-- 
Alessandro Pasotti
w3:   www.itopen.it
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Re: [Qgis-developer] PyQGIS standalone without x server

2014-10-28 Thread Martin Dobias
Hi Stefan

On Tue, Oct 28, 2014 at 5:47 PM, Ziegler Stefan stefan.zieg...@bd.so.ch wrote:

 Since I do not have access to a server w/o x server I cannot test it by 
 myself. Does anybody know if a running x server is required to run pyqgis 
 standalone apps? E.g. something like this:

 app = QApplication(sys.argv)

The X server is required here. QApplication will try to make a
connection to it. QCoreApplication does not - but it brings other
limitations.

Actually there is an easy way to try it out - just set DISPLAY env
variable to nothing:

martin@zenbook:~$ DISPLAY= python
Python 2.7.6 (default, Mar 22 2014, 22:59:56)
[GCC 4.8.2] on linux2
Type help, copyright, credits or license for more information.
 from PyQt4 import QtGui
 app = QtGui.QApplication([])
: cannot connect to X server

(the process is aborted)

Cheers
Martin
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Re: [Qgis-developer] QEP/RFC sqlite virtual tables

2014-10-28 Thread Hugo Mercier
Hi Matthias,

Le 28/10/2014 09:46, Matthias Kuhn a écrit :
 Hi Hugo,
 
 Sorry for my slow response, I was quite busy the last days.

With the 2.6 coming I know this is not the best time for this kind of
discussion :( So thanks for your time.

 
 I'll try to explain a bit more what I have in mind.
 
 For example there is the new expression function getFeature() which is
 an ad-hoc replacement for a join. I have been told that the performance
 for rendering is not very good, I assume this is caused by a lot of
 requests performed in the background. It would be great to be able to
 join this on the server side.

I agree. This getFeature() is a symptom that we need more advanced
relational-oriented functionalities.

 
 I would be very happy to see more of this introduced. For example I
 could well imagine a new Expression (Syntax just made up, that can still
 be designed in a more appropriate way)
 
   avg( c.population ) { LEFT JOIN cities c ON c.country_code =
 $thistable.code }
 
 This should then be locally evaluated (for shapefiles et al) but
 forwarded to the server for database services (postgres and the like).

How would it be forwarded for database services ? If the two tables
are from the same db, then ok, we are in the simple optimization case
that I was talking about previously : more or less a translation between
SQL dialects.
But what if the current table is a local file (shapefile) and cities is
a postgis table ?
You would then need a magical optimization engine that will say you need
to send the list of local country codes to a remote query like :

SELECT avg(population)
FROM cities
WHERE country_code IN ( $local_country_code_array )
GROUP BY country_code

But actually, the best optimization depends in the general case on the
actual data stored in tables. If the bandwith required to send the IN
part to PostGIS is too important, there may be cases where it is better
to fetch everything remotely and sort and group by locally or they may
be cases where another query would be better.

This is why writing an optimal SQL query is hard and why database
planners do lots of work, rely on lots of heuristics and statistics  and
are hard to implement.

 
 Now, as we have different backends and their syntax does not always
 match (most do standard sql, but there are extensions, think of ST_* in
 postgis, SDO_* in oracle spatial etc, and there is no guarantee, that a
 dataprovider supports standard SQL) we need an abstraction layer and
 cannot just assume that every dataprovider will understand the same thing.

Yes, exactly, and this was to whole point of relying on SQLite and
Spatialite as an abstraction layer.

 
 I am planning to implement this abstraction layer for ordinary
 expressions in the near future. And I would be very happy to see that
 there is a way to extend this with aggregate functions. This will all
 require a fallback level (if the server does not support a given
 functionality, for shapefiles, to be sure that the result is the very
 same regardless of server function implementation details...). We
 already have this for ordinary expressions as we can just use the
 QgsExpression implementation.
 
 I can only repeat, that I will be more than happy to see this fallback
 level implemented by means of sqlite virtual tables. But in my humble
 opinion it would be very unfortunate if there would be no way to
 optimize this tomorrow or the day after tomorrow. That's why I am asking
 if sqlite developers are open to collaborate because if the will to
 collaborate there is missing we will end up having to reimplement this
 functionality.
 
 I totally agree with your statement A general cross-database SQL
 optimizer would need lots of work (in QGIS and/or SQLite) and may come
 later (if really needed)., but would append and will require either a
 re-implementation in QGIS, ending up in duplicated functionality
 (that's what Régis was worried about in the original mail) or will need
 the possibility to get deeper access to sqlite's internal data
 structures or callbacks to optimize where required. This will require
 cooperation from SQLite developer's side or forking sqlite..
 

I really don't think the difficulty is here. Even if we have access to
the parsed SQL and even to the result of the SQLite planner, splitting
the execution plan in optimal local and remote operations is *very hard*
in the general case. And we would have to do it whatever the abstraction
layer we choose : SQLite or our own QgsExpression-based solution.
And I really don't think that would be a good idea to do this in QGIS.

The optimization plan could be: don't try to optimize in the general
case (premature optimization ...), only optimize specific
well-identified cases.
For now the only simple case I can see is when a join is done on tables
from the same database (and the user don't know or can't do a join on
the remote database), then yes we would have to know the syntax of the
original query and translate it into the desired 

Re: [Qgis-developer] QEP/RFC sqlite virtual tables

2014-10-28 Thread Matthias Kuhn
Hi Hugo

On 28.10.2014 12:15, Hugo Mercier wrote:
 Hi Matthias,

 Le 28/10/2014 09:46, Matthias Kuhn a écrit :
 Hi Hugo,

 Sorry for my slow response, I was quite busy the last days.
 With the 2.6 coming I know this is not the best time for this kind of
 discussion :( So thanks for your time.

 I'll try to explain a bit more what I have in mind.

 For example there is the new expression function getFeature() which is
 an ad-hoc replacement for a join. I have been told that the performance
 for rendering is not very good, I assume this is caused by a lot of
 requests performed in the background. It would be great to be able to
 join this on the server side.
 I agree. This getFeature() is a symptom that we need more advanced
 relational-oriented functionalities.

 I would be very happy to see more of this introduced. For example I
 could well imagine a new Expression (Syntax just made up, that can still
 be designed in a more appropriate way)

   avg( c.population ) { LEFT JOIN cities c ON c.country_code =
 $thistable.code }

 This should then be locally evaluated (for shapefiles et al) but
 forwarded to the server for database services (postgres and the like).
 How would it be forwarded for database services ? If the two tables
 are from the same db, then ok, we are in the simple optimization case
 that I was talking about previously : more or less a translation between
 SQL dialects.
 But what if the current table is a local file (shapefile) and cities is
 a postgis table ?

In this case I think the sqlite virtual table approach (or any other
local filtering method) should be preferred. That would involve too much
black magic.
There may be some cases where we can mix things (e.g. two parts of a
where clause combined with AND where only for one of the two WHERE
clauses a native SQL translation can be found could be performed as a
two-step filter, but that's really not the main point)

 You would then need a magical optimization engine that will say you need
 to send the list of local country codes to a remote query like :

 SELECT avg(population)
 FROM cities
 WHERE country_code IN ( $local_country_code_array )
 GROUP BY country_code

 But actually, the best optimization depends in the general case on the
 actual data stored in tables. If the bandwith required to send the IN
 part to PostGIS is too important, there may be cases where it is better
 to fetch everything remotely and sort and group by locally or they may
 be cases where another query would be better.

 This is why writing an optimal SQL query is hard and why database
 planners do lots of work, rely on lots of heuristics and statistics  and
 are hard to implement.

 Now, as we have different backends and their syntax does not always
 match (most do standard sql, but there are extensions, think of ST_* in
 postgis, SDO_* in oracle spatial etc, and there is no guarantee, that a
 dataprovider supports standard SQL) we need an abstraction layer and
 cannot just assume that every dataprovider will understand the same thing.
 Yes, exactly, and this was to whole point of relying on SQLite and
 Spatialite as an abstraction layer.

 I am planning to implement this abstraction layer for ordinary
 expressions in the near future. And I would be very happy to see that
 there is a way to extend this with aggregate functions. This will all
 require a fallback level (if the server does not support a given
 functionality, for shapefiles, to be sure that the result is the very
 same regardless of server function implementation details...). We
 already have this for ordinary expressions as we can just use the
 QgsExpression implementation.

 I can only repeat, that I will be more than happy to see this fallback
 level implemented by means of sqlite virtual tables. But in my humble
 opinion it would be very unfortunate if there would be no way to
 optimize this tomorrow or the day after tomorrow. That's why I am asking
 if sqlite developers are open to collaborate because if the will to
 collaborate there is missing we will end up having to reimplement this
 functionality.

 I totally agree with your statement A general cross-database SQL
 optimizer would need lots of work (in QGIS and/or SQLite) and may come
 later (if really needed)., but would append and will require either a
 re-implementation in QGIS, ending up in duplicated functionality
 (that's what Régis was worried about in the original mail) or will need
 the possibility to get deeper access to sqlite's internal data
 structures or callbacks to optimize where required. This will require
 cooperation from SQLite developer's side or forking sqlite..

 I really don't think the difficulty is here. Even if we have access to
 the parsed SQL and even to the result of the SQLite planner, splitting
 the execution plan in optimal local and remote operations is *very hard*
 in the general case. And we would have to do it whatever the abstraction
 layer we choose : SQLite or our own QgsExpression-based solution.
 

Re: [Qgis-developer] PyQGIS standalone without x server

2014-10-28 Thread Ziegler Stefan
Thanks!

Regards
Stefan 

 -Ursprüngliche Nachricht-
 Von: Martin Dobias [mailto:wonder...@gmail.com]
 Gesendet: Dienstag, 28. Oktober 2014 11:56
 An: Ziegler Stefan
 Cc: qgis-developer@lists.osgeo.org
 Betreff: Re: [Qgis-developer] PyQGIS standalone without x server
 
 Hi Stefan
 
 On Tue, Oct 28, 2014 at 5:47 PM, Ziegler Stefan stefan.zieg...@bd.so.ch 
 wrote:
 
  Since I do not have access to a server w/o x server I cannot test it by 
  myself. Does
 anybody know if a running x server is required to run pyqgis standalone apps? 
 E.g.
 something like this:
 
  app = QApplication(sys.argv)
 
 The X server is required here. QApplication will try to make a connection to 
 it.
 QCoreApplication does not - but it brings other limitations.
 
 Actually there is an easy way to try it out - just set DISPLAY env variable 
 to nothing:
 
 martin@zenbook:~$ DISPLAY= python
 Python 2.7.6 (default, Mar 22 2014, 22:59:56) [GCC 4.8.2] on linux2 Type 
 help,
 copyright, credits or license for more information.
  from PyQt4 import QtGui
  app = QtGui.QApplication([])
 : cannot connect to X server
 
 (the process is aborted)
 
 Cheers
 Martin
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[Qgis-developer] LizMap plugin: filter layer by user impossible to remove?

2014-10-28 Thread Paolo Cavallini
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1

Hi all.
Here, once set, the option reappears when closing and reopening LizMap
plugin: does anybody confirm?
Thanks.
- -- 
Paolo Cavallini - www.faunalia.eu
QGIS  PostGIS courses: http://www.faunalia.eu/training.html
-BEGIN PGP SIGNATURE-
Version: GnuPG v1

iEYEARECAAYFAlRPsJAACgkQ/NedwLUzIr4gPQCcCwC1niwpkaaEyp/YsoFLdFEG
wmAAn3uuivEFzst1CHkyb+IbbpUr5VnK
=jTqc
-END PGP SIGNATURE-
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Re: [Qgis-developer] QEP/RFC sqlite virtual tables

2014-10-28 Thread Hugo Mercier
Le 28/10/2014 13:21, Matthias Kuhn a écrit :
 Hi Hugo
 

 The optimization plan could be: don't try to optimize in the general
 case (premature optimization ...), only optimize specific
 well-identified cases.
 For now the only simple case I can see is when a join is done on tables
 from the same database (and the user don't know or can't do a join on
 the remote database
 ... or a developer wants to develop a provider-independent plugin/core
 functionality that has a good cross-table performance.

Do you have something in mind ?

 ), then yes we would have to know the syntax of the
 original query and translate it into the desired SQL dialect.
 And yes it would be better to have it from SQLite. It would require
 either to work with the developers, to patch it or to somehow include
 the parsing part of SQLite (we already ship sqlite / spatialite with
 QGIS right ?). But I really don't see it as a blocker.
 
 I don't think we do ship it but I may be wrong?
 Please don't get me wrong, I didn't say it's a blocker. The original
 discussion started from Régis statement there's a QEP taking care of
 relational queries, is there a need to duplicate functionality? and my
 response I am not sure if sqlite virtual tables will be able to satisfy
 all our needs. I was just wondering about the limitations of this
 approach and I am still very open to hear about any experiences you had
 with sqlite developers (I have none) because that is what counts when it
 comes to working with upstream as you proposed.

Indeed, I don't know well the sqlite dev community.
I will try to know a bit more about exposure of internal SQLite data
structures.
In the worst case we could decide to fork or include parts of the code
the license is very permissive.

Btw, there is a spatialite / sqlite source distribution in
src/spatialite (probably only used when WITH_INTERNAL_SPATIALITE is enabled)

 

 I really think using SQLite as our database engine has a good potential.
 It could extend the abilities and expressivity of QGIS. And it could
 also allow to use *less* code in QGIS (seeing every provider as a
 virtual layer). And it could also paves the way for a native QGIS file
 format (this is another discussion, but somehow related).

 But whatever the implementation is, trying to be (automatically) as
 performant as a well-designed query on a well-designed db is a waste of
 energy.
 Yes, we cannot do that. But we can try to find a way that allows
 developers to develop and users to create projects independent of
 providers while still providing good performance on a capable backend.
 

 On a more pragmatic side, people are already interested and might pay
 for db-oriented functionalities in QGIS (the very first need is to be
 able to filter joined tables). It does not have to be the only incentive
 for design choices, but this is a good opportunity. Then a decision has
 to be taken.

 So, if it is hard for you and me to agree :), are there other opinions ?
 Other arguments for one or the other side ?
 
 I don't want to disagree, I just wanted to raise questions / to
 understand the limitations. I see the demand for this functionality and
 I see the potential that sqlite virtual tables have to offer. I just
 wonder what the performance will be like in a scenario where there's a
 network (with latency for every request) involved. And what it would
 require to overcome this issue (if there is any).

Ok, but this performance issue is not related to the backend choice
(SQLite or our own), right ?

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Re: [Qgis-developer] QEP/RFC sqlite virtual tables

2014-10-28 Thread Régis Haubourg
Hi all, 
this is a very high level topic for me. I will just point out some
user/funder needs, and maybe try to describe other strategies exist in GIS
softs. 

As a user coming from both ESRI and Mapinfo world:

 - The main (and last?) real advantage of MI was its native pseudo-SQL
capabilities (with many limitations). Users really often now have a
centralized spatialDB, where the administrator can do many things (almost
everything in fact), but the classical user has only two possibilies for
relation Db treatments: algorithms or duplicate data in sqlite and learn
spatial sql (unless their DBA grant them to Postgres... ). Power users are
very happy, ex MI users are not in QGIS. 

- Arcgis have no agregate capabilities over its relations.. Joins are more
developped and allow summarize algoithms. To go further, It requires using
an external DB system, and it's a pain (they all have limitations, in term
of cost or learning curve..). Postgis/sqlite is far away in terms of
accessibility

Having virtual sqlite tables would allow some MI-like behaviour. Users here
would appreciate that a lot (I will still be using postgres underneath for
perfs).
 For more simple use cases, some only want to improve joins by being able to
join and output agregate values if multiples tuples join, for simple mapping
purposes. I think UI needs boths things, a SQL dialog to create queries -
Qspatialite-like - on every table, and some agregate capabilities over
joins. 
 What we must avoid is having two different implementations, with differents
limitations. Only power users knowing what is really happening underneath
will know what function to use, which is bad in UX terms. 
A comparison is OGR CSV driver versus CSV plugin... User has to know that
both tools are differents, behaves differently with a different providers.
Nothing in the GUI let you know that except try-fail approach.

BTW, I have the feeling you don't disagree at all but that we are digging
one of the harder features of a GIS tool. IMHO, that really desserves
discussions, prooves of concept.  Any other opinions in dev's?


Cheers
Régis



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