Null Geometries in Parcel Fabric

[JohnFell]

I'm curious if anyone has experienced errors or warnings related to null geometries in the subclasses and their published outputs from the parcel fabric. Our parcel fabric resides in an ArcSDE enterprise geodatabase for SQL Server 2008 R2. We recently had an ESRI tech support incident (1046926) where these geometries caused performance degradation for a spatial view. I also noticed that our ArcIMS map service was performing poorly as well. The current work around for fixing these null geometries is to export the features as a feature class in a file geodatabase, run the Repair Geometry gp tool, and then reimport into SDE. How do these null geometries get created? Is there a way we can avoid creating them?

[TimHodson · Accepted solution]

Hi John,

1. Regarding the performance problem that you reported, I'm sure you are already aware of this, but I wanted to post an update for the other forum readers: the performance slow-down is not connected with the empty geometries, it is a 10.1 specific problem that only affects queries on SQLServer with SDEBinary storage. There is a fix that will be available on 10.1 sp1, planned to be available in October 2012. (NIM082306)

2. Related to your questions about the null geoms: there is a technical difference between "null" geometries and "empty" geometries stored in geodatabases. Not all gdb platforms support "null" geometries, but empty geometries are supported across all gdb platforms. It's not certain if the case you indicate is for empty or null geometries. If there are null geometries getting exported, then that would indicate that there are also null geometries somehow getting stored in the fabric tables; these null geom records in the fabric table would be considered a problem, whereas empty geometries are expected.

The parcel editor creates empty geometries for the following cases;
On 10.0 fabrics:
1. unjoined parcels in the parcels table, (a saved construction falls in this category)
2. unjoined parcels' lines in the lines table
3. all radial lines in the lines table.

On 10.1 fabrics:
1 thru 3, above, and
4. unjoined parcels' points in the points table, but only if these points are not already in use by another joined parcel.

When creating the published parcel outputs, you could create queries that export the data to exclude the parcels that are unjoined.
For example:
(SystemEndDate IS NULL) AND "Joined" = 1

More info about joining parcels here.

Thanks for the feedback and for reporting the performance problem to tech support.

-Tim