Run a Feature Query

You can run a query on any feature property other than centerline. Criteria can be numeric or non-numeric.

Example 1

Create a simple collection of all rivers that are less than 20 meters wide, change the crossing type to three cells of a particular type of culvert, and change the color to a different shade of blue in order to highlight the new requirements.

Run this feature query

1. In the General tab, click on the Query icon.

2. Leave the Object field as Feature.

3. Under Property select Nature.

4. Leave the Operator as =.

5. From the Value list select River.

6. Click New set.

All of the Rivers within the study area are selected. The next step is to select those rivers that are less than 20 meters wide.

7. Open the Query dialog again. (See Step 1.)

a. Leave the Object field as Feature.

b. Under Property select Width.

c. From the Operator list select <.

d. From the Value list select 20.00

e. Click Select from set.

Note: When you click Select from set, the software creates a subset of the original set. The subset meets an additional criterion. You can keep repeating the process to create a final collection that satisfies three or four criteria.

Quantm Desktop software discards all rivers that are more than 20 meters in width.

8. Use the Feature Properties Box to make the required changes to the objects still selected from the query:

a. Change the Crossing type to Culvert.

b. Set Culvert type to 1500mm box.

c. Set the number of cells to 3.

d. Change the Color setting to the new color.

Example 2

Create a more complex collection that includes all roads wider than 20 meters and all rivers wider than 30 meters.

Run this feature query

1. Create a new layer called Temp.

2. Create a collection of all roads wider than 20 meters. Follow the method described above, but set the Operator field to >.

3. Put the road collection into the new Temp layer.

4. Create a collection of all rivers wider than 30 meters. Move these to the layer called Temp.

Note: When you click Add to set, the software adds objects that meet the new criterion to the original set.

5. Select all features in the Temp layer. To do this, run a query to select all features in the layer Temp, or open the layer Temp in the Layer pane and then directly select all objects in the layer.

Next topic: Run a Zone Query