[QGIS-Developer] Fwd: [Qgis-user] Editing a multipolygon object changes type from Multipolygon to Polygon

[Jörg Höttges]

Hi everyone,

I'm using QGIS 3.16 to 3.22. I created a table with multipolygon objects in a SpatiaLite database. When editing one of 
the polygons there appears a warning "Die Operation würden Geometrietyp ändern" ("The operation would change geometry 
type") and saving of the changings failes.

Following are the objects before and after the modification:

before editing:
wkt_geom: MultiPolygon (((379698.83699999999953434 5709466.37000000011175871, 379705.34999999997671694 
5709460.93499999959021807, 379703.7970000000204891 5709459.07600000035017729, 379697.34799999999813735 
5709464.77400000020861626, 379698.83699999999953434 5709466.37000000011175871)))

after adding the point (379701.02700000000186265 5709464.54299999959766865):
wkt_geom: Polygon ((379701.02700000000186265 5709464.54299999959766865, 379705.34999999997671694 
5709460.93499999959021807, 379703.7970000000204891 5709459.07600000035017729, 379697.34799999999813735 
5709464.77400000020861626, 379698.83699999999953434 5709466.37000000011175871, 379701.02700000000186265 
5709464.54299999959766865))

how can I make sure that the type does not change due to editing? The only idea i have is to remove or modify the 
geometry constraint in the Spatialite database table for the geometry column. The warning still appears but saving is 
successful.

Interesting fact: The problem didn't appear with QGIS 3.16.

Many thanks for your help!

Jörg Höttges

-------
FH Aachen
University of Applied Sciences
Bayernallee 9
52066 Aachen | Germany
www.fh-aachen.de/menschen/hoettges

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/qgis-developer/attachments/20220401/18ad3e13/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/pkcs7-signature
Size: 5991 bytes
Desc: S/MIME Cryptographic Signature
URL: <http://lists.osgeo.org/pipermail/qgis-developer/attachments/20220401/18ad3e13/attachment.bin>