Hi Lynn & John,

Personally, I don't think that combined date fields are adequate, particularly for retrospective data capture.  We have far too many insect labels with partial dates (tiny labels, tiny print, no room), which really mess up (probably also platform dependent screwups) when you try to enter the data as a date without one of the pieces.  We've found all permutations--year only, month and year, month and day, well, maybe not day and year...but that's enough of a variety that we have all the fields individually broken out to accomodate this and then account for missing data in a calculated "pseudo" date by making assumptions depending on which piece may be missing.  It also gives you greater flexibility and assuredness that you have the day and the month able to be put in the order desired or show the date in different formats such as 6.ix.1956, where the day and the month could easily be confused.

Cheers!
Gail

Hi Lynn,
 
XML Schema, in its dateTime type, supports a subset of the ISO 8601 datetime standard. The proposal for DwC2 currently recommends the concepts EarliestDateCollected and LatestDateCollected, both as dateTime types, to capture bounded or unbounded date/time combinations of arbitrary specificity. These should be sufficient except where lists of dates or other multiple date ranges are required for a single record - unless I'm missing something, in which case I'd like to know.
 
Cheers,
 
John

 
On 2/23/06, Lynn Kutner <Lynn_Kutner@natureserve.org> wrote:
Hi -
I'm working with a suite of date attributes that can include a combination of precise dates, imprecise dates, and ranges of dates (and the same types of time values). We'd like to follow existing standards. If this sort of date / time standard exists, I'd appreciate leads to the appropriate resources.
Thank you for your help -
Lynn

Lynn Kutner
Data Management Coordinator
NatureServe
Email:    lynn_kutner@natureserve.org
Phone:   (303) 541-0360
www.natureserve.org


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Gail E. Kampmeier
Sr. Research Entomologist
Illinois Natural History Survey
Box 5 NSRC, 1101 W. Peabody Dr.
Urbana, IL 61801
http://www.inhs.uiuc.edu/~gkamp
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