## Dissolve Boundaries

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Areas that overlap or share a common boundary are merged together to form a single area.

You can control which boundaries are merged by specifying a field. For example, if you have a layer of counties, and each county has a State_Name attribute, you can dissolve boundaries using the State_Name attribute. Adjacent counties will be merged together if they have the same value for State_Name. The end result is a layer of state boundaries.

## Choose dissolve method

You can choose one of two methods for merging area features:

- Areas that overlap or are adjacent—Two or more areas whose boundaries overlap each other will be merged into one area. In addition, areas that are adjacent (that is, they share a common boundary) will be merged into one area.
- Areas with the same attribute value—Areas that overlap or share a common boundary will be merged into one area if they have the same attribute value.

  For example, if you have a layer of counties, and each county has a State_Name attribute, you can dissolve boundaries using the State_Name attribute. Adjacent counties will be merged together if they have the same value for State_Name. The end result is a layer of state boundaries.

If Use current map extent is checked, only the features in the analysis layer visible within the current map extent will be dissolved. If unchecked, all features in the analysis layer will be dissolved, even if they are outside the current map extent.

## Summarize area attributes

When areas are merged, you can summarize their attributes. For example, if you are dissolving the boundary between counties based on State_Name, and each county has a Population attribute, you could calculate the sum of Population for the state.

Available statistics types are:

- Sum—Adds the total value for the specified attribute.
- Average—Calculates the average for the specified attribute.
- Minimum—Finds the smallest value for all records of the specified attribute.
- Maximum—Finds the largest value for all records of the specified attribute.
- Std. Deviation—Finds the standard deviation on values in the specified attribute.

## Result layer name

This is the name of the layer that will be created in My Contents and added to the map. The default name is based on the analysis layer name. If the layer already exists, you will be asked to confirm if you want to overwrite it.

Using the Save result in drop-down box, you can specify the name of a folder in My Contents where the result will be saved.