Polygon Overlap is Sliver

Available with Data Reviewer license.

Summary

Sliver polygons are usually small polygons resulting from overlay operations such as Intersect or Union. Sliver polygons typically have and 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:

ValidationConstraint

Reviewer batch job

Reviewer map rule

Attribute (validation) rule

No

Yes

No

Yes

(ArcGIS Pro 2.9 or later)

Syntax

Parameter Required DescriptionWorkflow

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

Features to Compare Filter

No

A query that identifies the features to include in the rule.

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.

    Learn more about spatial references

  • The Validation Status attribute value of both the input features and data sources included in the Features to Compare parameter are ignored during evaluation. For example, input polyline 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 Features to Compare 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.
  • Include the data source for the Features to Compare parameter when sharing web layers with the Validation capability enabled.

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