Bug report #13983
Split parts on MultiLineString: discards data
|Affected QGIS version:||2.12.0||Regression?:||No|
|Operating System:||Windows 7 x64||Easy fix?:||No|
|Pull Request or Patch supplied:||No||Resolution:||end of life|
|Crashes QGIS or corrupts data:||No||Copied to github as #:||21997|
The issue is that geometry data is silently discarded when using the Split Parts tool on MultiLineString geometries with QGIS 2.12.1-Lyon (16760fd).
Consider a simple MultiLineString in a PostGIS database:
MULTILINESTRING((0 0, 10 0))
Editing the geometry with the Split Parts tool (in the Advanced Digitizing toolbar), e.g., to split the line in the middle will do this: keep only the MultiLineString from the start to the split location, and discard the MultiLineString from the split location to the end, such as
MULTILINESTRING((0 0, 5 0)).
An expected result would be something like
MULTILINESTRING((0 0, 5 0), (5 0, 10 0)).
A second experiment with
MULTILINESTRING((0 0, 5 0), (5 0, 10 0)) will show data loss of other parts that were not split. Splitting the first part will keep the line from the start to the split location, and will discard both the remaining portion of the first part, and all of the second part, so result is
MULTILINESTRING((0 0, 2.5 0)). Furthermore, splitting the second part will discard all of the first part, and keep only the start of the second part to the split location, so result is
MULTILINESTRING((5 0, 7.5 0)).
An expected result would keep the other parts of the geometry, as well as the new parts that were split, so either
MULTILINESTRING((0 0, 2.5 0), (2.5 0, 5 0), (5 0, 10 0)) or
MULTILINESTRING((0 0, 5 0), (5 0, 7.5 0), (7.5 0, 10 0)).
#2 Updated by Giovanni Manghi 7 months ago
- Resolution set to end of life
- Status changed from Open to Closed
End of life notice: QGIS 2.18 LTR
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