SCR 3-1033

SCR 3-1033: Local Data Dictionaries

Priority: medium

Problem Summary

Adopting keywords into the PDS data dictionary typically requires a fair amount of negotiation between CN and the group (DN and/or the instrument team) proposing the new keyword(s). The negotiation is centered around ensuring that the keyword is accurately defined, does not conflict with an existing keyword, complies with the formation and class-word rules, uses the proper set of units, etc.

The group reviewing the proposed keyword is also responsible for providing a keyword definition that has a long term scope of use across missions, instruments, and data products. While this process can be tedious and time consuming, it does ensure that the set of approved keywords adhere to a level of “quality assurance”.

The PDS has come to realize that:Certain data producers (e.g., flight missions) seek to include keywords with narrowly defined meanings – presumably useful only within the mission and, sometimes, only for a single instrument. Magellan produced a lot of these, but they were pushed through the full approval process and now populate a non-trivial fraction of the PSDD.There are also instances in which data providers wish to “reuse” existing keywords with new meanings – sometimes merely refined, sometimes rather different.The PDS approval process for new keywords has broken down. There aren’t enough people and there isn’t enough time to process all of the requests (particularly the mission-specific and instrument-specific requests) while keeping up with everything else we’re supposed to be doing. In many cases the special keywords have little or no meaning to people outside the discipline, so it is difficult to marshall enthusiasm for the full approval process. Or, argued a little differently – PDS has not developed a sufficiently efficient keyword ingestion procedure to keep up with the requests.

Working Group

S. Hughes (lead) A. Raugh, R. Joyner, L. Huber, J. Wilf, R. Alanis, T. King, J. Zender

Originator: S. Hughes

Standards Change Request


Supplementary Material


StatusDateTaskResponsible PartyResponse
SUBMITTED 2002-11-14
IN_PROGRESS 2003-02-20
DRAFT 2003-06-05
APPROVED 2003-06-19
RELEASED 2003-08-07