General Considerations

General Considerations

Null Data

Most NULL data, if it can be migrated and is required in BrM 7.x, will be replaced with “Replace Me”. The data can then be searched and modified in BrM 7.x. The only exceptions are Bridge.OvertoppingLikelihood and Superset fields which are replaced with “???” due to field length.

SNBI Mappings

Note that BrM 7.x stores data in SNBI format. Most data migrations will have transformation mappings from the coding guide value to the SNBI format. For example BRIDGE.RAILRATING value of 0 translates to “I0-T” (see here). Mapping information is available on the FHWA crosswalk and mapping sites. The sections below will not detail all mapped data as the information is available by viewing the SQL scripts and the FHWA site. It would be prohibitively verbose to detail all mappings in this document.

• https://www.fhwa.dot.gov/bridge/snbi/datacrosswalk.cfm
• https://www.fhwa.dot.gov/bridge/snbi/codemapping.cfm

Migration Update Logic

Note that each block of script in the migration is a run-once script. However, many scripts contain UPDATE statements or MERGE statements with updates. The updates are legacy logic - originally it was assumed users could be running BrM 6.7.1 and BrM 7.x in parallel and need to repeatedly run the migration script. Practically, running the script multiple times presents some challenges, and it was decided to make each block a run-once script. However, to preserve the code in case it could be useful in the future, many UPDATE statements remain in the script.