Bug report #5224

'Merge selected features' tool creates invalid MULTIPOLYGON instead of POLYGON geometry

Added by Ivan Mincik over 12 years ago. Updated over 5 years ago.

Status:Closed
Priority:Normal
Assignee:-
Category:Digitising
Affected QGIS version:master Regression?:No
Operating System: Easy fix?:No
Pull Request or Patch supplied:No Resolution:end of life
Crashes QGIS or corrupts data:No Copied to github as #:14960

Description

In some cases, 'Merge selected feature' tool creates invalid MULTIPOLYGON instead of possible single POLYGON geometry.
This makes a problem in case, when layer supports only single POLYGON geometries. This problem can be avoided, when all nodes of one of the features are moved and returned back to the same place using 'Node tool' before merge.

Example data is attached. I also did test with merging the geometries using PostGIS - correct single polygon was returned.

SELECT
ST_GeometryType(
ST_Union(
ST_GeomFromText('POLYGON)'),
ST_GeomFromText('POLYGON)')
)
)

st_geometrytype 
-----------------
 ST_Polygon
(1 row)

Qgis: latest release-1_7 branch
OS: Debian Squeeze
Geos: 3.2.0-1

qgis-merge.zip (1.91 KB) Ivan Mincik, 2012-03-23 05:10 AM

History

#1 Updated by Paolo Cavallini over 12 years ago

  • Target version changed from Version 1.7.4 to Version 1.8.0

#2 Updated by Paolo Cavallini almost 12 years ago

  • Target version changed from Version 1.8.0 to Version 2.0.0

#3 Updated by Nathan Woodrow over 11 years ago

  • Assignee deleted (Nathan Woodrow)

#4 Updated by Jürgen Fischer about 10 years ago

  • Target version changed from Version 2.0.0 to Future Release - Lower Priority

#5 Updated by Giovanni Manghi over 7 years ago

  • Regression? set to No
  • Easy fix? set to No

#6 Updated by Giovanni Manghi over 5 years ago

  • Resolution set to end of life
  • Status changed from Open to Closed

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