Road Ahead – Merge Conflicting Geometries

A conflict on the geometries or the shape attribute of a feature class will arise any time the shape has changed on the same feature in the two different versions being reconciled.

At 9.2 and earlier ArcGIS releases, if there was a conflict on the shape field only one representation could be chosen. We didn’t really think this made sense because there were many cases where the geometry changes occurred in different parts of the shape, why couldn’t these changes be merged together? At 9.3 they now can with new functionality added by the geodatabase team for merging conflicting geometries during a reconcile operation.

 

This conflict occurs at the field level and is associated specifically with the Shape attribute. The option to merge geometries is available when there is a conflict concerning the Shape field. If two editors both edit the geometry of the same feature but do not edit the same area of that feature, they now have the option to resolve the conflict by merging geometries and accepting both edits.

The option to merge geometries is only available on the Shape field shortcut menu.

Once the geometries are merged, the end result is a feature that contains the edits made by both editors:

If the edits made by one editor share a region that was also edited by another editor, their edited areas will overlap. Although the option to merge geometries may be available, trying to do so will fail.

This entry was posted in Geodata and tagged , , . Bookmark the permalink.

Leave a Reply

4 Comments

  1. amitnalla says:

    Very useful. How will this work with complex geometries?

    Thanks,
    Amit

  2. brentardenpierce says:

    Hi Amit,

    What do you mean by complex geometries?

    -Brent

  3. drewdowling says:

    As I understand it this only be possible if the same vertices’s have not been edited in each version. Is this how it works or is there some kind of distance buffer from the geometry change?

  4. brentardenpierce says:

    Our implementation of this follows this logic:

    When merge geometries is called we calculate the area that has been edited on each shape. We do this by creating a minimum bounding rectangle or envelope which contains all edited vertices (including adjacent verticies that have not been explicitly edited). These envelopes (one for each version) are compared and if they intersect a merge will be disallowed.

    The case where only one vertex has been modified on each version follows the same logic but in this case the envelopes will contain only 3 vertices. Why three? The one edited vertex and two adjacent vertices.

    Hope this helps.