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I want to locate or highlight all the holes (invalid interior rings that do not connect at all vertices and edges) and redundant geometry in a polygon shapefile in QGIS so that I can go back and manually correct all the vertices and geometry. I do not want to use the "Delete Holes" tool because I want to do it manually.

Some of the potential holes are very small, so it would take me a long time to find them all

Example image with one hole below

enter image description here

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    Please Edit the original closed question instead of adding a new one. Locate or find holes tool in QGIS for polygon shapefiles Note that your definition of invalidness needs work, since interior rings ("holes") are a valid part of most topologic datasets, as are external rings ("islands")
    – Vince
    Commented Jan 26 at 17:23
  • No, that was my previous question but I did not attach a picture like I did in this question. All of the geometry is valid in my shapefile
    – MapDeath
    Commented Jan 26 at 17:27
  • I don't understand the jargon of how to ask my question the way you want me to
    – MapDeath
    Commented Jan 26 at 17:28
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    And we don't understand your Question using our jargon in unknown ways. Interior rings never "connect at all vertices"; they, in fact, are forbidden from touching at more than one. Maybe you should start with the shapefile specification, so you understand what valid rings are, and then you can focus on how QGIS gives programmatic/manual access to the data structure.
    – Vince
    Commented Jan 26 at 17:37
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    The person who posted the answer below figured out what I was trying to ask
    – MapDeath
    Commented Jan 26 at 18:47

1 Answer 1

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Try this workflow: enter image description here

My starting layer, some holes along the borders and inside: enter image description here

  1. Dissolve enter image description here

  2. Delete holes enter image description here

  3. Difference the Delete holes output with the start layer to create polygons where there are holes enter image description here

The output is one multipolygon, you might want to Multipart to Singleparts it to create individual polygons of each part/hole.

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