Project Summary

Project image thumnail

GIS Applications Maintenance and Database Migration

Upgraded custom GIS applications as well as previous clustered databases

Project Problem

Cook County was seeking a qualified contractor to upgrade all custom GIS applications to the ESRI software version 9.3. The applications used a number of ESRI 9.2 version products to serve a number of agencies and business processes. This migration to 9.3 was necessary in light of the County’s planned upgrade of its enterprise GIS, including ArcGIS and ArcSDE, to the 9.3 level. The GIS was managed in ArcSDE utilizing IBM DB2 as the relational database management system, and included cadastral, planimetric, administrative, census, terrain, and raster data.

The County also required the upgrade of their previous clustered DB2 SDE databases from 9.2 to 9.3, and wanted to explore the option of upgrading to SQL Server 9.3.

Project Solution

Great Arc along with subcontractors ESRI, SCARFE Consulting, and GISBiz, comprised a project team with a wealth of direct experience with County applications as well as with the underlying technologies and industry best practices. Great Arc had previously migrated the County’s parcel maintenance application using a replicated version of the County environment at our offices using virtual servers. We updated this replicated environment, ensuring it represented the current County technology, and were able to leverage it for this project as well. This development environment allowed us to easily back up, test, and restore server configurations during the project development/migration tasks, and gave us a method to fully test the upgrade of each of the applications at our offices to ensure that all issues were identified and resolved prior to implementation at the County.

For this project, Great Arc utilized a phased approach. Initially, we established a baseline for all of the existing applications by reviewing all existing County test cases and creating any necessary test cases for all functionality. In this way, all application functionality was documented prior to the upgrade, and these test cases would also serve as validation following the upgrade to ensure that all functionality had been implemented correctly.

The next phase was to implement the upgrade at our office. We created a backup of the replicated County environment, including the clustered DB2 test and production servers, ArcIMS web servers, SQL Servers and desktop client machines, then they were upgraded to ESRI version 9.3.1, after which we then upgraded the applications and data likewise to 9.3.1.

For the County’s desired migration from DB2 to SQL Server, ESRI worked on-site to review the County’s existing systems and provided recommendations as to the best practices for the setup and ongoing maintenance of ArcSDE in SQL Server.

Following this, Great Arc worked with the County to install and configure the Enterprise SQL Server ArcSDE systems, and then proceeded with the data migration process to copy spatial and attribute data from the enterprise DB2 database into the SQL Server test environment at Great Arc’s offices.

Following the installation and testing of the upgraded applications in Great Arc’s replicated environment, we invited County staff to verify the applications at our offices prior to installation at the County to ensure that all components were functioning as expected. We then moved on to repeat the upgrade and installation process in the County test environment. All application test scripts and processes were run against the applications in the test environment. Once all testing was completed in test, the applications were then installed on the production environment, and the final round of testing was performed, ensuring an efficient implementation with minimal down-time for the County.

Full documentation was provided for all aspects of the project, including updated system architecture documentation, installation plan and instructions, GIS system acceptance test plan, and user guides.



  • ArcSDE
  • SQL Server
  • ArcIMS
  • ArcObjects
  • AJAX
  • ArcGIS
  • DB2
  • ActiveX