Cadastral Framework Project Meeting Minutes
February 3, 1999 Q:\docs\CadastreFW\Project Mgt\Communications\Integration\mtg990203minutes.wpd
Marc Thomas, USBLM
Larry Holmes, USBLM
Greg Tudor, WADNR
Dave Steele, WADNR
Wes Schlenker, Longview Fibre
Rusty Nance, Longview Fibre
Frank Fisher, WADNR
Charlie Ware, WADNR
Tim Young, WADNR
Curt Kiessig, Snohomish County
Don O'Connell, Snohomish County
John Sharrard, ESRI
Kevin Kozak, WADNR
Steve Kimsey, WADNR
Barbara Putnam, WADNR
Ron Torrence, WADNR
Jeff Devitt, ARIS
Greg Tudor, Cadastral Framework Project manager, facilitated the meeting. Introduced ourselves, our interests in the project.
Reviewed the databases of Framework, Snohomish County, Bureau of Land Management, Longview Fibre, and DNR Aquatic Resources. The physical model of the framework implementation was given out to each partner organization. Conversion of PLS-PT points will be completed in 1-½ weeks, Major Public Lands in 2-3 weeks, and DNR ownership shortly thereafter. Snohomish County's Integrated Land Records are now in a region coverage with townships, sections, government lots, 1/4 sections, tax lots, and administrative areas. Snohomish County is currently updating their corner location information with a control survey. Snohomish County is starting to work with SDE layers. City of Everett is working with Snohomish County through an interlocal agreement. BLM is continuing to develop GCDB files for Snohomish County and has completed 16 townships, with 19 more underway, and plans to complete the county within the next year or so. The BLM Oregon Office received $30,000 to complete the GCDB coding for the county and contribute the data to the framework database. An example of a township coverage of GCDB data showed the extent of the records research and calculation necessary to show section subdivision into sixteenths and government lots, meander lines, and mineral surveys. Longview Fibre has coverages with corners and ownership to contribute. DNR Aquatic Resources reviewed the vectorization of protraction plates with subdivisions of aquatic land.
The scope of the integration was examined. The integration will focus on Legal Area Descriptions, Boundaries, and Corners. There is a natural progression of development and population of the framework cadastral database. Corner information is needed first for location of Legal Area Descriptions. Legal Area Descriptions must be developed before Parcels can reference them. DNR will complete the first cut conversion of its own data, transfer it to the framework database, and publish it on the framework server. DNR's Aquatic Resources division will use the data transfer standard to integrate their data. BLM will concentrate on collecting information to complete the GCDB coding and subdivision of PLS into sixteenths and government lots.
Several approaches to the data integration process were reviewed. The first was the current scope of development for the pilot project. DNR will populate the framework database with data from an internal conversion of DNR POCA, PLS-PT, and MPL data. Partners will be able to download framework data to use or upload data for integration. Uploaded data will be transferred across the firewall to an edit environment on DNR's internal side of the firewall. DNR will develop integration processes internally which later be used on the framework server. Integrated data will be transferred across the firewall to the framework database. Specifically, DNR will populate the framework database with legal descriptions, corners, and boundaries. BLM will download the framework data to incorporate into the GCDB coding and subdivision into sixteenths and government lots. BLM data will then be formatted in the data transfer standard and uploaded to the for integration into the framework database. DNR, Snohomish County, and Longview Fibre will contribute information to BLM as needed. DNR research from the Public Land Survey Office is not assured since PLSO has a state mandate to charge fees for their services and no funding has been designated to allow DNR to contribute those services.
After the pilot development of the data transfer standard and integration processes, the integration processes developed internally in DNR will be implemented on the framework server. DNR will then use the same process as other partners to download data for use and upload data to contribute for integration with the framework database. A resolution database will have to be implemented on the framework server at that time. The process will be for data to be downloaded from the framework database for use, data provider partners to upload data to the framework server, data would be integrated into the resolution database, and moved over to the framework database after validation and data conflicts are resolved. Partner access to the resolution database would allow partners to resolve problems with minimal integrator effort.
A new concept was introduced, termed self-integration, which would require data providers to resolve data conflicts to the extent possible. The data provider would contact the data provider who is the current owner of data in the database. The ownership information would come from the audit fields which show who updated a file row last and when it was last updated. The two data providers with conflicting data would have to decide which data should be retired and which should be included in the database.
Several types of notification were identified. Project notification would be sent out when partners noted that they were to be starting data collection work in an area; this would be used by potential project partners to coordinate project work. Check-out notification - when partners were actively changing data in an area; this would be used by other data providers working the same vicinity to coordinate their updates. Check-in notification - when data had been successfully checked in to the framework database; this would be used to notify partners and other framework theme coordinators that new data had been added to the database. Conflict notification - when data had not been accepted into the database because it conflicted with data already there; this would be used by the data provider to work with the previous data provider to determine which data should reside in the database in a self-integration process. Integration rules will be established once work with the data sets has started.
A brief discussion of transaction, long transaction, and transaction versioning reviewed the current technology status. Transactions normally occur on-line and must be completed before they are applied and accepted by the database. The normal transaction mode will be used for the pilot project. Feature locking will not take place until the data provider is ready to check data into the database. Long transactions allow the database connection to be broken and a certain amount of time to elapse without canceling the transaction. The update features are locked until the transaction is canceled or completed (pessimistic locking); no others could check out the data. Long transactions could be written in Oracle now, but would require considerable effort. Long transaction should be available for network features with new releases of ESRI software SDE 4.0 and Arc 8.0 in July. Transaction versioning (long transactions with optimistic locking) allows two users to check out the same data concurrently. When data is checked in, changes are tracked and any conflicts with subsequent updates are flagged for resolution by the data provider. Transaction versioning should be available for network features with SDE 4.0 and Arc 8.0. In Arc 8.0, spatial features will be database objects with properties and behaviors which can be used for integration automation. Long transactions and versioning will not be available for 2-D (polygon) features until Arc 8.1 is released. Charlie Ware is going to Redlands for training on Arc 8.X beta so that he can evaluate the software. BLM is working with ESRI directly on the GeoComm initiative to allow project notification and some ways to incorporate cadastral features into the database.
Data Transfer Standard
Discussion of the data transfer standard reviewed the pros and cons of several approaches to developing a transfer standard. The FGDC Cadastral Data Transfer Standard is a normalized ESRI regions export coverage. That approach is good for transferring a whole project, but has not been working well for sending transactions across the Internet. The approach we are taking is to denormalize the data and package all parts of an individual update transaction together. In the conversion process, DNR has found that making the transition from a complex structure to a simple data structure to a different complex data structure is easier than making a direct transition from a complex data structure to another complex data structure. The approach facilitates developing just one procedure for integrating data in the data transfer standard format into the database. The approach also reduces the number of relations that would have to be reestablished in the integration process.
The details of constructing a denormalized data transfer standard were resolved by going through the data model and noting which tables would be included in the Corner, Boundary, and Legal Area Description transfer files. The Corner transfer file will include Corner, Corner Point, Coordinate Measurement, Plane Coordinate System, Land Area Document, and Land Agent. The Boundary transfer file will include Boundary, Boundary Measurement, Land Area Document, Land Agent, and Survey Measurement. Legal Area Description transfer file will include Legal Area Description, PLS, PLS Section Subdivision, Non-PLS, Land Area Document, Land Agent. All three data transfer files will include the audit fields Updated By, Date Created, and Date Updated. The coordinates of all spatial features will be in latitude/longitude GRS80 NAD83. Corner coordinates may also include their originally established coordinate measurements and appropriate datum information as attributes.
Discussion of the spatial transfer format indicated that further testing was required to establish a transfer standard. ESRI shape files and export coverages are being considered at this time. DNR will draft the transfer standard files for review in two weeks.
1. Draft the self-integration process - Greg Tudor.
2. Develop the data transfer standard and specifications for Corner, Boundary, and Legal Area Description. Distribute in PDF format via e-mail and web site - Greg Tudor.
3. Provide examples of Internet updates - Jon Sharrard.
March 3, 1999