Available with ArcGIS Pro Standard and Data Reviewer licenses.
Summary
Sliver polygons are usually small polygons resulting from overlay operations such as Intersect or Union. Sliver polygons typically have an area that is much smaller than the perimeter. The Polygon Overlap is Sliver check finds overlaps between polygon features that are below a specified thinness ratio.
Overview
The purpose of the Polygon Overlap is Sliver check is to find overlaps between polygon features that are slivers based on their shape and, optionally, size. Sliver overlaps between polygon features often result from creating polygon features without proper snapping settings or from editing shared boundaries without a topology.
When configured as a validation rule, an error is created for each feature that shares a boundary with a sliver overlap.
Supported workflows
ArcGIS Data Reviewer checks support multiple methods for implementing automated review of data. The following table identifies the supported implementation methods for this check:
| Validation | Constraint | ||
|---|---|---|---|
Reviewer batch job | Attribute (validation) rule | No | |
Yes | Yes (ArcGIS Pro 2.9 or later) | ||
Syntax
| Parameter | Required | Description | Workflow |
|---|---|---|---|
Subtype | No | The subtype to which the rule is applied. | Validation |
Attribute | No | A query that identifies the features to which the rule is applied. | Validation |
| Features to Compare | Yes |
Input features are returned as errors based on their relationship to the features from this data source. Valid inputs are polygon features. | Validation |
Filter | No | A query that identifies the features to include in the rule, from the data source specified in the Features to Compare parameter. | Validation |
| Thinness Ratio | Yes |
The ratio (T = 4π(A/P²) between the overlap area (A) and its perimeter (P). A thinness ratio of 0 is a perfect circle and 1 is a line. Overlaps between polygons with a thinness ratio less than this value are considered errors. | Validation |
Maximum Area | No | The maximum overlap area that is considered a sliver overlap. Overlaps between polygons that are below the thinness ratio and equal to or less than this value are considered errors. The default unit of measure is the unit of measure used by the input data source's horizontal spatial reference. | Validation |
| Name | Yes | A unique name for the rule. This information is used to support data quality requirement traceability, automated reporting, and corrective workflows. | Validation |
Description | No | A description you define of the error when a noncompliant feature is found. This information is used to provide guidance to facilitate corrective workflows. | Validation |
| Severity | Yes | The severity of the error assigned when a noncompliant feature is found. This value indicates the importance of the error relative to other errors. Values range from 1 to 5, with 1 being the highest priority and 5 being the lowest. | Validation |
| Tags | No | The tag property of the rule. This information is used in rule authoring and management workflows to support traceability and reporting of data quality requirements. | Validation |
Notes
Keep the following in mind when using the check:
- The data sources of the input features and Features to Compare parameter must share a common datum.
- The Validation Status attribute values of both the input features and the data sources included in the Features to Compare parameter are ignored during evaluation. For example, input features with a validation status of 0 (No calculation required, no validation required, no error), 1 (No calculation required, no validation required, has error(s)), 4 (Calculation required, no validation required, no error), or 5 (Calculation required, no validation required, has error(s)) are still included during rule evaluation.
- The Attribute and Filter parameters are limited to comparison (=, <>, >, <, >=, <=) and logical (AND/OR, IN/NOT IN, LIKE/NOT LIKE, IS NULL) operators.
- Data sources for the Features to Compare parameter must include a global ID field.
- Errors are returned for overlaps that are greater than the x,y tolerance of the spatial reference.
- Include the data source for the Features to Compare parameter when creating map or project packages and when sharing web layers with the Validation capability enabled.