See the following topics for more information including how to setup and review Base and Alt. LRMs:

Data Model

Once the alternate referencing is defined in the SETUP_LOC_REF_COLUMNS table and the changes applied to the database, the columns configured there will appear in the SETUP_LOC_IDENT table (refer to Chapter 4, for in-depth understanding and information about other uses of this table). In order to support translation between the base and Alt. LRMs, as shown in the following figure, the system requires a full map between them.

The mapping between the base and alternate is provided by a special set of rows in the SETUP_LOC_IDENT table. These rows are always identified by the row filter: SOURSE_TABLE='LOC_REF_XX' (where XX is the ID number of alternate referencing system from SETUP_LOC_REF).

This set of rows in SETUP_LOC_IDENT must always be a full map between all references in the alternate system mapped onto the base system. When editing and viewing data the system utilizes these records to calculate a base reference when given an alternate and vice versa. The example in the next section shows as an example. Records corresponding to the table SETUP_LOC_IDENT – LOC_REF_25 Sourse_Table are displayed (in this example, LOC_REF_ID for the Alt. LRM is 25). The LOC_IDENT is a unique identifier in this table and contains information about each route segment mapping between the Base and Alternate Referencing System – Attribute Columns (Route Number, County, Direction, Functional Class, etc.) and the Measure Columns (State-wide Milepost From/To, etc.).


There is no Alt LRM configured out of the box, but if you have created an Alt LRM, when you right-click the record for an alternate LRM in the upper pane, the system displays the following special command in a shortcut menu:

The steps are shown in the following charts.

Add a menu item under this parent

Example Alternate LRM Mapping Screen

SETUP_LOC_IDENT Table Data with a County-Based LRM Example