Esri ArcGIS Pro Foundation Certification Practice Test

Which overlay analysis method writes all of the input geometry to the output feature class?

1. Erase

2. Intersect

3. Spatial Join

4. Union

The correct answer is: Union

The Union overlay analysis method is designed to combine multiple input feature classes, retaining all the geometries from each input and merging their attributes into a single output feature class. This means that the output will contain not just the spatial information, but also the attributes from all layers involved in the analysis. This method is particularly useful when you want to preserve all data rather than limiting it to shared or overlapping features. In contrast, other methods, such as Erase, Intersect, and Spatial Join, have different functionalities and do not retain all input geometries. Erase removes parts of one feature based on another, and Intersect only includes areas where input features overlap, resulting in a more limited output. Spatial Join relates attributes from one layer to another based on spatial relationships but does not create a new geometry that includes all inputs. Therefore, the Union method is the only technique that guarantees the inclusion of every input geometry in the final output, making it the correct choice for the question.