Route identifiers (IDs) can consist of a single field in the route table or several fields. Coded value domain fields are supported as one or more fields in a concatenated route ID. When you create an LRS Network, you need to understand how your business tables are going to reference routes. Your route table must have a record for every unique route ID, which can mean a record for every unique combination of fields that may make up a route ID.
These records do not have to be unique in the route table, as only the first instance of the ID encountered will be used. However, each unique combination that makes up a route ID must be included. See Creating an LRS Network and Using concatenated route identifiers for more information about creating LRS Networks with concatenated route IDs in the linear referencing system (LRS).
Because the Roads and Highways editing tools must insert values into fields in the route table to create a new route record, there are certain rules you must follow when creating concatenated route ID fields.
- Concatenated route IDs can either use a field separator or not, but all route IDs within a network must follow the same convention.
- Some LRS Networks may have concatenated fields with separators, and other LRS Networks may have concatenated fields without.
- If you do not use field separators, your field length can be either fixed or variable.
- If you will not fill the maximum length of a field when creating a route, add padding to fill the remaining characters.
- The total length of your route IDs—with separators and empty spaces—in fields composing your concatenated route ID may not exceed the field used to store route IDs in your calibration point feature class.
When creating your LRS Network with a concatenated route ID, you have the option to allow fields to have padding added to the route ID for fields shorter than the maximum length. An example would be a route ID composed of three fields: State, which is a string with a length of 1; County, which is a string with a length of 3; and Section, which is a short integer with a length of 5. In this scenario, the County field could have values ranging from 0 to 999. To ensure the route ID for the network has the same number of characters for each route, a padding character of 0 could be added to the County field in the route ID. If a value of 1 for State, 7 for County, and 19245 for Section were entered when creating a route, 1 would be entered in the State field in the route table, 7 would be entered for the County field in the route table, 19245 would be entered for the Section field in the route table, and 100719245 would be entered as the route ID.
Similarly, you have the option to allow fields in the concatenated route ID to be null. Any field in the route ID can be null. However, if a field is null, all the fields to the right in the route ID must also be null. An example would be a route ID composed of three fields: RouteType, which is a string with a length of 1; Route, which is a short integer with a length of 5; and RampNumber, which is a string with a length of 2. Some of the created routes will not have a RampNumber; therefore, that field can be configured to be null when creating your LRS Network. If a value of 3 for RouteType, 26645 for Route, and nothing for RampNumber were entered when creating a route, 3 would be entered for the RouteType field in the route table, 26645 would be entered for the Route field in the route table, <null> would be entered for the RampNumber field in the route table, and 326645 would be entered as the route ID.
Additionally, a lookup table can be configured for one or more fields in the concatenated route ID. A lookup table is an alternative to using coded value domains when there are hundreds or thousands of values, such as a GNIS code or street names. The lookup table can be configured with both display and key fields. The key field is the value that will be saved for the field in the concatenated route ID; the display field is the value that appears in the text box in the multi field Route ID dialog box. The key and display fields can be different fields in the lookup table or the same field. In the multi field Route ID dialog box, the lookup table field has IntelliSense. After typing three characters in the text box, a list of matching records in the lookup table appears. The list updates as additional characters are entered. Once a value is selected, the display field value appears in the text box and the key field value appears to the right of the text box, and as part of the route ID at the top of the dialog box. Any padding configured for the field will be added if the key value is shorter than the field length. If the desired value is not present in the lookup table, you add the value to the lookup table. Roads and Highways only reads the lookup table; it will not add records to the table.
- Start ArcMap and set up your editing environment to start editing LRS Networks that use concatenated route IDs.
- Set your target LRS Network layer on the Roads And Highways Editing toolbar.
- Click the Choose Centerlines button
on the Roads And Highways Editing toolbar. - Click a centerline on the map at the location of the new route.
- Click the Create Route button
on the Roads And Highways Editing toolbar.The Create Route dialog box appears.
- Click the Start Date drop-down arrow to choose a start date for the route.
The time is automatically populated with 12:00:00 AM by default.
- Click the browse button
next to the Route ID text box.The RouteId dialog box appears and shows the fields that have been configured to construct route IDs. The dialog box will be slightly different depending on whether a field separator, a coded value domain, a lookup table, or padding for fields is used. As you populate the dialog box, the route ID appears at the top.
RouteId dialog box when no field separator is used 
RouteId dialog box when no field separator is used, but padding is enabled for Route field 
RouteId dialog box when coded domain values are used 
RouteId dialog box when a lookup table is used 
RouteId dialog box when a field separator is used - Populate the route ID field text boxes.
When no field separator or padding is used
Enter a value into each route ID field, ensuring each text box is completely filled.
When no field separator is used with padding
Enter a value into each route ID field. If you use less than the maximum number of characters, padding will be added.
When a coded value domain is used
Choose the domain value from the list of domains in the drop-down list.
When a lookup table is used
Enter the key or display (depending on configuration) value in the text box.
When a field separator is used with or without padding
Enter a value into each field that makes up the route ID.
When you begin adding numbers to the route ID field text boxes, you will see that the numbers to the right of the text boxes increase.
- When you complete each field in the route ID, click OK.
- When you finish populating the Create Route dialog box, click OK to complete the route.