Integration of Legacy, Cots, And Map Data
Discrepancies
Since records systems have been maintained by human beings, potentially using imperfect
systems, even in a situation where synchronization, freezing, and match-keys were not problems,
discrepancies between the data in the systems will exist. These discrepancies will be identified
through a sound data integration process. The findarnental question then is what to do when
discrepancies are identified during database construction. The following options essentially
describe the options.
- Resolve each Discrepancy on a Case-by Case Basis, Report the Resolution
- Resolve each Discrepancy on a Case-by Case Basis, Do Not Report the Resolution
- Resolve Discrepancies based upon Standard Rules, Report the Resolution
- Resolve Discrepancies based upon Standard Rules, Do Not Report the Resolution
- Report Discrepancies
- Ignore Discrepancies
Determination of the most appropriate strategy for dealing with discrepancies must be carefully
and thoroughly considered. Discrepancy resolution, either during or after database construction
may be a very time-consuming and expensive undertaking. Conversely, ignoring discrepancies
may be inappropriate.
Data Maintenance
The maintenance of data during and after its use in the construction of the integrated geospatial
database will be significantly impacted by the implementation of system. In a well-designed
system, the data maintenance processes will be more consistent, faster, and more efficient than
its predecessor processes. This gain however, is only achievable through some pain.
During the database construction and data integration processes special data maintenance
procedures may be required, alternatively it maybe possible to postpone data maintenance
during the freeze period, postponing the maintenance effort and creating a "backlog" of records
posting activities. Additionally, in cases where synchronization of existing datasets prior to
integration was not feasible, special data maintenance activities aimed at achieving
synchronization after database construction may be required. Optional approaches to addressing
this database maintenance requirement include the inclusion of some backlog posting process
within the database construction process, and the limited-term use of additional records posting
personnel.
The successful long-term use of the geospatial system and its component datasets will require
that all data maintenance requirements are addressed and that all data maintenance activities are
well understood. Gaining this understanding and developing appropriate procedures will require
the detailed assignment of data maintenance responsibilities and the thorough analysis and
design of data maintenance workflows.
Conclusion
The integration of disparate datasets is an essential requirement of geospatial system
implementation. Many implementers have underestimated the data integration challenge and
under-invested in the analysis of data integration issues prior to beginning geospatial database
construction. Successfidly addressing data integration challenges is a critical sub-task of
successful geospatial database construction.
While the challenge is often substantial, the issues are predictable and can be addressed through
appropriate consideration and procedure development.
