Selecting events by attribute

Use the Select Events by Attribute widget in the Roadway Characteristics Editor to select events on a map by querying the event layer's attributes. This method of event selection uses Structured Query Language (SQL) WHERE clauses to select events on the map using one or more criteria.

For example, if you want to select all the events within Route 10054101 that have a speed limit greater than or equal to 40 miles per hour, write an SQL expression such as "Route_ID" = '10054101' AND "Speed_Limit" >= 40.

To learn more about building SQL expressions, see Building a query expression.

步骤:

1. Open a web browser and browse to the Roadway Characteristics Editor.
2. Select the event layer on which you want to run the query using the Layer drop-down list.

   You can navigate the list of layers by keystroke. For example, press the S key in the drop-down menu to jump to the first layer in your list that begins with the letter s.

3. Click the Edit tab and in the Selection group, click the Select drop-down arrow to select Select by Attributes.

   The Select by Attributes widget appears.

4. Double-click a field to add the field name to the expression box.
5. Click an operator to add it to the expression.
6. Click Get Unique Values to see the values for the selected field.
7. Double-click a value to add it to the expression.
8. Follow steps 4 through 7 to add other conditions to the expression.

   Steps 4 through 7 can also be skipped if you know the SQL WHERE clause to type. In that case, just type the WHERE clause.

9. Click Select.

   All the records in the SpeedLimit layer with a Route_ID of 10054101 and a speed limit greater than or equal to 40 miles per hour are highlighted on the map. The results are shown in a tabulated format.

Once the event records are selected, browse to and edit them using the results grid. See Editing events in the selection table for more information.