Event types
Events are created by registering event tables with Esri Roads and Highways in the ALRS Properties dialog box or by right-clicking the LRS Network in the Catalog window.
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注:Prior to registering the events, it is highly recommended that you have the appropriate indexes created to improve performance in your event tables and ensure the registration process is not slow due to lack of database indexes.
Internal and external events
Event layers are either internal, meaning they reside within the geodatabase that houses your ALRS, or external, which means they reside outside of the geodatabase. External events can be stored in another geodatabase, an Access database, a dBASE file (.dbf), an Excel spreadsheet, or in any other enterprise database such as Oracle, SQL Server, and so forth. Besides the location of the source table, internal and external events also have a major difference with respect to how they are managed after registration.
Internal events are managed in feature classes, called the event feature classes, in which Esri Roads and Highways manages the shape of the feature based on the route, measure, and to and from dates. This provides increased performance in ArcGIS for mapping and spatial query of the event data. When registering an internal event, you can register either a feature class or event table. If you register an event table, the data is copied into a feature class in order to support the storage of the shape on the event and from that point forward.
When external events are registered, the event layer is drawn as an ArcGIS event feature layer that always reads the source table as the authoritative source.
Reference offset events
Esri Roads and Highways supports registration of simple events and reference offset events. When registering events, you specify a route ID and measure columns to inform Roads and Highways how to locate the events on the network. When registering reference offset events, you locate events based on an offset from the location of another entity. In some cases, that entity could be another event, point feature class, or X- and Y- coordinates.
There are five different types of events that can be created: