October - December 2005
The Geodatabase Designer can export and import an XML design from an existing geodatabase. (Note: There is no way to generate a VISIO template from an existing geodatabase.) VDOT found this useful for replicating a few changes, such as topology rules or assigned spatial references, that could not be modeled in Visio. For improved readability, the Geodatabase Designer tool was used to export the Designer XML from a geodatabase first built on the Visio XML. This modified XML was used to create a new geodatabase structure.
The process flow was as follows:
This tool was used to create a Visio presentation stub diagram from a geodatabase. Esri uses this to generate part of its object model diagrams and posters.
VDOT used the SDELoader tool to calculate recommended spatial extents, precision, and grids used in configuring the spatial references for the feature datasets.
VDOT customized the ArcObjects EditorID tool to track the user name and time stamp of any edits to the features or table rows in the geodatabase. This required adding two new fields, EditorName and LastUpdate, to each table as a data model modification.
Some Caveats about Networks, Versioning, and Topology
No specific tools for managing the transportation-specific network or DOT-specific business requirements and reporting were included with the UNETRANS model, and using the editing tools in ArcMap can cause some problems. VDOT discovered that a topology and a network could not be applied to the same feature dataset at the same time. Network editing tools caused all related table information to be orphaned when an existing road segment was split. The split tool, when used with topology editing, did not break the link to related tables.
Topology editing did not automatically orphan the old links, and the existing links were cached in the attribute editor. To speed data loading, as recommended for initial loads, VDOT dropped the network and then rebuilt it using the Geodatabase Designer tool to export just the network or topology designs.
Every day, each user creates a version for all editing activity. At the end of the day, all edits are reconciled and posted, and the version is deleted. An ArcSDE batch process was put in place to automatically compress and analyze the geodatabase each night.
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