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1
vote
2answers
44 views

Polygon inside polygon invalid in QGIS

Looking at this map data from naturalearth (part of Oman & UAE to be specific), each country is defined as a multipolygon. In this case UAE (in red) contains two polygons and Oman (beige) three. ...
2
votes
1answer
241 views

Detecting invalid WKT in text column in SQL Server

I've got a whole load of WKT data in a SQL Server table, of which I'm trying to detect the validity. I'm currently doing a query like this: UPDATE f SET f."CurrentGeomValid" = ...
3
votes
1answer
346 views

Possible solution for dangling nodes?

I was just asked in a interview what a dangling nodes was. I had no idea and asked a former co-worker. I was informed that a significant amount of time was spent fixing these. I was confused how ...
4
votes
2answers
701 views

Why are self-intersecting polygons bad?

Working with both ArcGIS and Oracle Spatial, a self-intersecting polygon renders a geometry invalid. Why are self-intersecting polygons a problem?
2
votes
2answers
343 views

ArcSDE: Specifying fields to not allow null values

I have a feature class in SDE that has various fields where the setting AllowNulls is set to FALSE. When creating a feature in ArcMap in this feature class it still allows nulls to be specified in ...
3
votes
1answer
102 views

Help obtaining nodata information for ASTER datasets

Is there any way to determine what the nodata value should be, in a set of geotiff images that do not have the 42113 tiff tag ? I am trying to get elevation information, programatically in c++, and I ...
2
votes
2answers
285 views

How to implement field validation rules in ArcGis?

Not digging in deep, I've found that ArcGis offers validation of 2 basic constraints: field data type and if the value is required or not. Is there any way or AddIn to attach more complex validation ...
2
votes
1answer
327 views

validate SDE features within arcObjects (cant use sdeLayer)

I'm trying to sweep through a feature class checking for invalid features (and log the invalid features). Would IValidation.Validate work or does that just check for rules? If not I'm guessing I ...
3
votes
4answers
2k views

Is there any place in which I can find a list of invalid database characters for ArcGIS 10?

Relating to my question about the split tool here, as suggested I ask a new question: is there any place with a list of invalid characters to use in a database in ArcGIS 10? edit: It is in relation ...
9
votes
3answers
344 views

Invalid geometry zoo

Many a time and oft I've spent hours struggling with bizarre bugs resulting from invalid geometries. The symptoms vary greatly, including: Database slowdowns Incorrect\Null query results Log files ...
2
votes
3answers
483 views

Why is this polygon “self intersected” and invalid?

I have a polygon defined as follows: segment from 43:29:02 N 003:50:39 E to 43:34:12 N 003:43:04 E arc(CW): center (43:34:49 N 003:58:16 E) from 43:34:12 N 003:43:04 E to 43:45:45 N 003:59:56 E ...
9
votes
2answers
970 views

What are the implications of invalid geometries

I've imported some data in a Postgis database and some of the geometries are reported invalid (ST_IsValidReason reports self-intersection or ring self-intersection). The queries I am performing don't ...