I am digitizing a new polygon shapefile of property boundaries based on orthoimagery using QGIS Zanzibar. I'm acquainted with topology editing in ArcMap using geodatabases. I did so with snapping to vertices and segments enabled.

Using the Topology Checker Plugin in QGIS 3.8 Zanzibar and in 3.6 Noosa I can identify digitizing errors such as gaps and overlaps.

enter image description here

However when attempting to use v.clean in the Processing window I keep running into the following errors:

WARNING: Concurrent mapset locking is not supported on Windows
WARNING: Column 'id' : type int8 (bigint) is stored as integer (4 bytes) some data may be damaged
WARNING: Column 'id' : type int8 (bigint) is stored as integer (4 bytes) some data may be damaged
WARNING: Unable to create index
WARNING: Unable to copy table <Block_6_Parcels_Test> for layer 1 from <vector_5d9f8b040caf72@PERMANENT> to <output39ece58e87d34cfa8e0b689616f7aafc>
WARNING: Failed to copy attribute table to output vector map
WARNING: Number of centroids exceeds number of areas: 7 > 5
WARNING: Number of incorrect boundaries: 2
WARNING: Number of centroids outside area: 2
ERROR: Key column <> not found
WARNING: No areas found, but requested to be exported. Will skip this feature type.
WARNING: No attribute table found -> using only category numbers as attributes
WARNING: Output layer is empty, no features written

I have two fields that could be used as key fields, either the id column that is the default generated first column when you create a new shapefile, or the PARCEL_ID. Both are created as @row_number in field calculator. Both are populated.

I've tried just doing one error rule at a time (i.e. fixing gaps first with v.clean only, then fixing overlaps with v.clean) but both fail. I've tested this in both 3.6 Noosa and 3.8 Zanzibar.

How should I go about fixing my topology? A link to the shapefile https://www117.zippyshare.com/v/vhZODckl/file.html

  • The link points to a 403, can you please update it? Oct 11, 2019 at 8:25
  • 2
    You may want to check the new topological cleaning tool (QGIS plugin) developed during the ECMWF Summer of Weather Code 2019, see mundialis.de/en/…
    – markusN
    Oct 11, 2019 at 19:53


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