If a topology contains many smaller polygons, you can create a new topology by combining polygons that share the same data value in a specified field. This field is called the dissolve field.
To dissolve a composite topology
- In Map Explorer, right-click the topology to dissolve .
- In the Topology Dissolve - Set Parameter dialog box, for Dissolve By, specify the data element to use for the new topology. To select a field from an object data table or a column from an external database, click (Expression Evaluator).
Any two adjacent polygons or connected lines that have the same value for the specified field or column are combined into a single polygon or line.
- In the Topology Dissolve - New Topology dialog box, select Highlight to highlight the resulting topology onscreen. Specify the highlight color.
- Enter a name and description for the new topology and specify the layer. Click Next.
- In the Topology Dissolve - Output Attributes dialog box, do the following:
- Click (Expression Evaluator) to select the data to include in the resulting topology. You can include fields in an object data table or columns in an external database.
- Enter a name and description for the object data table that will store the data in the new topology.
- Click Next.
- In the final dialog box, indicate whether to create new nodes to complete the resulting topology. If so, specify which a block to use:
- To use a point, leave the box blank or enter ACAD_POINT.
- To select from a list of block definitions, click the down arrow.
- To select a block saved as a DWG file, click Browse. Select the file to use.
If you are dissolving a polygon topology, you can also specify the block to use for centroids.
- Click Finish to dissolve the topology.