Configuring padding, null, and lookup table settings

When creating an LRS network, you have the option to add padding and allow null records for each field in the route identifier. This is especially useful if external business systems utilize a specific RouteID definition and are not able to change. The RouteID for the network within Roads and Highways could then have padding or null settings added to conform to the legacy RouteID format of the external system. For example, a RouteID could be configured with four fields: County_Code, City_Code, Section, and Ramp_Number. County_Code is a short integer field with a length of 5. The maximum number of characters that will be entered for any RouteID is 3; however, some routes may have 1 or 2 characters entered for this field. City_Code is a string field type with a length of 3, but the field will have values ranging from 0 to 999 entered. Section is a string field with a length of 6 and a lookup table configured to allow the user to search for the key value using a display field. The Ramp_Number field is a long integer field with a length of 10; however, some routes will not have a value for this field and need to be left blank.

Each field in the RouteID can have the maximum length shortened, be variable or fixed length, have padding characters added to the left, right, or both left and right side, and have padding added to an empty field. Additionally, a null value can be used for one or more of the fields in a concatenated RouteID. Additionally, a lookup table of key values can be configured for any fields that are a part of the concatenated RouteID. The RouteID for each record will be stored with padding and null values included. Each individual field used as part of the concatenated RouteID will be stored without any padding settings. An example of creating a route with padding, nulls, and lookup table enabled is shown below.

Tip:

These settings will be used during route loading and when using Roads and Highways editing activities, such as creating routes.

The record for the newly created route in the network attribute table shows padding added to the RouteID field but not the individual fields that compose the concatenated RouteID. While the display value was used to search for the Section field in the multi field RouteID dialog box, the Key field value was populated for the section field in the database and as part of the concatenated RouteID. The field left empty during route creation has a null value in the attribute table.

1. Model your data in your source routes based on the padding and null settings you want for each field. The concatenated RouteID field should include padding, but each individual field should not include padding. For example, you have a field called RouteType, a string field with a length of 6 is part of the concatenated RouteID that you want to pad with zeroes on the left side. The value for the field in one of the routes is 89. You would not include the padding in the Route field of your source routes (89) but would include the padding for the RouteType portion of the RouteID field (000089).



Note:

These settings can be changed once the network is created. Any routes loaded and created before changing these settings remain saved in the database as is. Any route loaded and created after changing the settings use the updated settings when being saved in the database.

2. The Length field defaults to the length of the field in the database. The range for the field can be any number between 1 and the default. The value entered will be the maximum number of characters that field can contain within Roads and Highways. You should determine the maximum number of characters any route in your network will use for each field and set the length to at least that value.

   Note:

   Changing the length only changes the maximum number of characters Roads and Highways expects for each column as part of a route in the network. Your data should still be modeled within your geodatabase with the RouteID field length being the sum of the lengths of the fields composing the concatenated RouteID.

3. Choose whether the field will be Fixed Length.
   • If the field will always be populated with the number of characters selected in the length field in step 2, check the Fixed Length check box. This ensures the number of characters in the length field is required in routes being loaded or created in Roads and Highways.
   • If the field will have a variable number of characters, uncheck the Fixed Length check box. This allows for the number of characters in the field to range from 1 to the number selected in the length field in step 2 for routes being loaded or created in Roads and Highways.

   Note:

   Having multiple fields that are variable length could result in duplicate route IDs composed of different values in the concatenated fields being loaded or created.

4. Check the Enable Padding check box if you want padding for the field.
5. Select your Padding Character.

The padding character can be a number, space, or other character.



6. Click the Padding Location drop-down arrow and select an option for the field.

   Padding can be added to the left, right, or both left and right of the characters in the field.

7. Check the Pad If No Value Provided check box to add padding characters to the portion for that field within the RouteID and have a null value placed in the field.

   Note:

   The Allow Null Values check box is automatically checked if you check the Pad If No Value Provided check box.

8. Check the Allow Null Values check box if you want to support null values in the field.

   Note:

   If you allow null values in a field, all fields to the right of that field must also allow null values. However, if you also check the Pad If No Value Provided check box, fields to the right do not have to allow null values.



9. If one or more fields in your network has a table with lookup values, click the Lookup Table button for that field and browse to the location where the table is located in your geodatabase.

   Note:

   A lookup table is an alternative to using coded value domains when a field that makes up the concatenated RouteID has several hundred or thousands of potential values. An example would be a list of street names or a GNIS code. The table can have a Key and Display field configured, allowing a user to search for a Key value using a Display value. The lookup table would be primarily used in the Create Route editing activity.

   If your lookup table is in a multiuser geodatabase, the table should be unversioned.

10. Click the Lookup Key Field drop-down arrow and select a field.

    Note:

    The Lookup Key Field value will be saved in the geodatabase for both the field and as part of the concatenated RouteID.

    The only options that appear in the list will be the same field type with a length less than or equal to the length configured in step 2.

11. Click the Lookup Display Field drop-down arrow and select a field.

    Note:

    The Lookup Display Field is optional. If you want to allow a lookup value that is not in the table, you should not configure a Lookup Display Field value.

12. Check the Allow Any Lookup Value check box to allow a value not present in the lookup table for the field in the concatenated RouteID.

    Note:

    If you check the Allow Any Lookup Value check box, you can't configure a Lookup Display Field value.