Bug report #7540
Merge tool bug when a shapefile is loaded multiple times
Status: | Closed | ||
---|---|---|---|
Priority: | Severe/Regression | ||
Assignee: | - | ||
Category: | Digitising | ||
Affected QGIS version: | master | Regression?: | No |
Operating System: | Easy fix?: | No | |
Pull Request or Patch supplied: | No | Resolution: | fixed/implemented |
Crashes QGIS or corrupts data: | Yes | Copied to github as #: | 16483 |
Description
Hi !
When a Shapefile is loaded multiple times (either in the same project via "duplicate layer" or in two different QGis instances), there is a critical bug upon merging features.
Both merged parts simply disappear without any error (though it seems sometimes QGis crashes).
To reproduce:- create a new shapefile (line or polygon)
- enter edit mode
- draw a feature and split it several times with the scissor tool
- exit edit mode
- duplicate the layer
- enter edit mode on one of the two layers
- select two line segments and merge them with the merge tool
- exit edit mode
- reload the project and see!!
Related issues
Associated revisions
ogr provider: reopen the data source if a REPACK failed (fixes #7540)
Repack shapefiles when saving after deleting features
- QgsVectorDataProvider::dataChanged() will be emitted
- QgsVectorLayer::dataChanged() will be emitted
- Clears QgsVectorLayerCache
- Reloads the attribute table
- Clears the selection
Looking forward to people complaining about their lost selection...
Fix #10560
Fix #11989
Refs #8317
Refs #8822
Refs #10483
Refs #11007
Refs #7540
Refs #11398
Refs #11296
History
#1 Updated by Giovanni Manghi over 11 years ago
- Status changed from Open to Feedback
it is a regression since 1.8? I'm not able to replicate the issue here, but maybe I'm doing it wrong.
#2 Updated by Olivier Dalang over 11 years ago
Yes it's a regression, the problem does not show up in 1.8...
Here (Windows 7) it seems to happen every time when following those steps.
If confirmed, this should be a blocker, since it leads to data corruption.
#3 Updated by Giovanni Manghi over 11 years ago
- Priority changed from Normal to Severe/Regression
#4 Updated by Radim Blazek over 11 years ago
9) reload the project and see !!
What does it mean "reload the project"? Reopen project file or refresh display?
#5 Updated by Olivier Dalang over 11 years ago
- on the layer that was not edited, you see that the two merged parts have disappeared
- on the layer that was edited, you see the two merged parts plus the result of the merge
But actually, I'm just discovering that the shapefile seems in a deeper mess, even after reloading : if you create a new polygon, no matter what shape, it will take the shape of the result of the merge.
Here's a screencast of the procedure :
https://www.dropbox.com/s/84nj515s6mfu09f/mergeBug2.avi?m
#6 Updated by Giovanni Manghi over 11 years ago
- Status changed from Feedback to Open
#7 Updated by Giovanni Manghi over 11 years ago
- Category set to Digitising
#8 Updated by Salvatore Larosa over 11 years ago
is it still true ?
following the above steps I did not get any crash !
tested with a polygon layer and I do not see unusual behavior.
#9 Updated by Giovanni Manghi over 11 years ago
following the above steps I did not get any crash !
tested with a polygon layer and I do not see unusual behavior.
I don't think it causes crash, it causes data corruption.
#10 Updated by Jürgen Fischer over 11 years ago
- Status changed from Open to Feedback
Giovanni Manghi wrote:
I don't think it causes crash, it causes data corruption.
So you can reproduce the problem? Just checking, if I should try harder...
#11 Updated by Giovanni Manghi over 11 years ago
So you can reproduce the problem? Just checking, if I should try harder...
no I can't.
Olivier still true for you?
#12 Updated by Olivier Dalang over 11 years ago
Hi !
The behavior changed a little bit but I still get data corruption (with master from yesterday, under Windows 7).
It's no more necessary to reload the project to see the data loss.
Here's a screencast : https://www.dropbox.com/s/g70fkaus6j40vll/mergeBug4.avi
#13 Updated by Jürgen Fischer over 11 years ago
- Status changed from Feedback to Open
ok, I can reproduce it now. I suspect it's a file locking issue in OGR (might be tied to windows). Looking into GDAL now...
#14 Updated by Jürgen Fischer over 11 years ago
- Assignee set to Jürgen Fischer
#15 Updated by Jürgen Fischer over 11 years ago
- Status changed from Open to Closed
Fixed in changeset 78b04df91a1b85ee70ff5b326980f480b3069d47.
#16 Updated by Jürgen Fischer over 11 years ago
Jürgen Fischer wrote:
Fixed in changeset 78b04df91a1b85ee70ff5b326980f480b3069d47.
It was caused by locking. QGIS does a REPACK after deleting and that silently fails with current OGR. GDAL pull request #17 should fix this by adding an error message. reopening the original DBF if it can't be removed and cleaning up the *_packed.dbf
.
Nevertheless QGIS now checks if there still is a *_packed.dbf
to detect that the REPACK failed and reopens the dataset in that case.
#17 Updated by Giovanni Manghi about 10 years ago
- Status changed from Closed to Reopened
- Target version changed from Version 2.0.0 to Version 2.6
Sorry to reopen this, seems master still affected. See also #11082
#18 Updated by Jürgen Fischer about 10 years ago
- Assignee deleted (
Jürgen Fischer)
#19 Updated by Giovanni Manghi about 10 years ago
it is pretty easy to replicate this issue, it is just needed to "insist" a bit. Here two screencast, that as some point show that after removing a shape and re-adding it features are lost!
The second show also a possible bug in the "split features" tool.
#20 Updated by Giovanni Manghi about 10 years ago
Giovanni Manghi wrote:
Sorry to reopen this, seems master still affected. See also #11082
after all it does not seems related... I have a VM with qgis running against gdal/ogr trunk and I can still see the issue described in this ticket.
#21 Updated by Giovanni Manghi about 10 years ago
- Status changed from Reopened to Feedback
it seems this could have been solved by this 4cf08c5c112278ab4f50cf21b735a4a58d6a98aa
#22 Updated by Jürgen Fischer about 10 years ago
- Target version changed from Version 2.6 to Future Release - High Priority
#23 Updated by Giovanni Manghi about 10 years ago
- Status changed from Feedback to Closed
- Resolution set to fixed/implemented
after 4cf08c5c112278ab4f50cf21b735a4a58d6a98aa I really cannot make to replicate this issue. That commit solves also partially #11007 (but only for the case of edited features, still there is an issue with deleted ones).
Please reopen if necessary.