Select the holes in a vector shapefile in QGIS

Question

Is there a way to select the holes (gaps) in a vector shapefile in QGIS, like the "fill holes" function which recognizes them indirectly?
I need to get the holes from the original shapefile and work with them.
Is there a way in other software like Arc?

MrXsquared · Accepted Answer

If you dont mind a two step process:

Run "Delete Holes" from processing toolbox on your "PolygonWithHoles"
Run "Difference" and use your "Cleaned" (Result from Delete Holes) as Input and your "PolygonWithHoles" as Overlay:

Result:

MrXsquared · Answer

If you wish a one-step solution, you could also use "Geometry by Expression" with this expression:
difference(make_polygon(exterior_ring($geometry)),$geometry)

or a "virtual layer" with this query:
select difference(make_polygon(exterior_ring(geometry)),geometry) from PolygonWithHoles

Both will return a multipolygon of the holes.

Select the holes in a vector shapefile in QGIS

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