Introducing Geographic Information Systems with ArcGIS: A Workbook Approach to Learning GIS, 3rd Edition

Topology Rules

Geodatabase topology is based on rules that define the required spatial relationship between two feature classes, or sometimes specify a requirement within one feature class. For example, a rule might be that no two polygons may overlap each other. Currently, there are thirty-some rules defined in the software. Below you will choose a rule that says that the points of one feature class must be covered by (that is, have a point coincident with) a feature in a given line feature class.

____ 7. Press Add Rule. In the Add Rule window, select Fire_Hydrants in the Features of feature class drop-down menu. Click the down arrow in the Rule text box to see the rules. There are six rules that relate to point feature classes. List them below:

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____ 8. Select the rule Point Must Be Covered By Line, since we want the water lines to go to Fire_Hydrants. The third text field (Feature Class) should indicate Water_Lines. Now give your attention to the right side of the window, where ...