Invalid geometries are loaded into a file geodatabase without detection. These invalid geometries can come from a shapefile, personal geodatabase or another file geodatabase via import/export or copy/paste.
The source for the invalid geometries is always a shapefile created outside of ArcInfo Workstation or ArcGIS, which cannot create incorrect geometries, but does copy them.
Examples of invalid geometries:
· Self intersecting polygons
Multipart polygons can not overlap within a geometry.
· Unclosed polygons
All parts of a polygon must close. The last vertex of a polygon ring should be the same as the last vertex. While the polygon fill algorithm used in ArcGIS draw polygons correctly that do not close correctly, the geometries remain invalid.
· Single point polygons and lines
Polygon must be composed of at least three points. Lines must be composed of at least two point.
· Incorrect polygon ring direction
The vertices of the outer ring of each polygon must be in clockwise order. A polygon may contain multiple outer rings. Holes are counter clockwise. If the outer rings or holes are not following the proper ring direction, the geometry is invalid.
Solution or Workaround
Run the Geoprocessing Repair Geometry tool, which is available under Data Management Tools > Features, on the feature class.