The below is solvable by appropriately designing the metadata model. One such solution could be: publication dates: 2003/ record last updated: 20110321 If the publication ends in 2015 and a user examines the record in 2016 they can clearly see that from the state of knowledge in 2011... The record last updated data is relevant to all kinds of other content.. not just dates.. even the name could change--- is this is new journal and the end of the old or a continuation of the same journal under a new name? The journal "Psychiatry 2010"--- indexed as Psychiatry (Edgemont)-- has changed its name, for example, this year to Innovations in Clinical Neuroscience. Is this a new journal? Should its publication dates listed as 2004/ ? Or new record and the old one is 2004/2010 and a new record 2011/ ? All these are correct and possible (and it is not up to me to decide).. The bottom line: any value in a bibliographic record is only from the state of knowledge the editor had at the time of the last update to the record.. perhaps another (additonal) field is appropriate: record last checked: 20111021 This can indicate through the difference between "record last updated" and "record last checked" .... (and again, its not up to me to decide upon ones profile resp. model..) IN Bib1 we have 1011 Date/time added to database 1012 Date/time record last modified On Sat, 19 Mar 2011 17:41:47 +0100, [UTF-8?]Saašha Mets�rantala wrote > Hello! > > > Since permissions are an on-going > > thing they are clearly defined by an > > interval (many of a series of incremental > > dates) rather than a single point > > (date) within a continuum. "publication > > dates of journals or other serially > > issued resources" that are still being > > published--- and to which no plans > > have been expressed to cease > > publication--- are clearly defined too by > > "open ended" intervals. > OK! We need open-ended intervals. In the light of the examples above, an > attendant question is immediately rising: Should open-ended intervals > (always) contain only ONE date? > > Let's assume that journal J was first published in 2003 and is still > published as of today. We can encode that as an open-ended interval > begining in 2003, but then, the information "as of today" would not be > recorded there (read below). The concept of "today" is varying with time - > every day. At a later date, someone reading such a record containing the > open-ended interval may wonder when this information was recorded and if > such information is not available, this person will not be given more > information than "journal J was first published in 2003". The open-ended > interval would loose accuracy and be reduced to a (semantically) > non-interval "date of first publication". > > On the other hand, if we choose to encode open-ended intervals with TWO > dates, we could express something like: "Journal J was first published in > 2003 and was still regularly published as of 2011". Such an encoding would > make it possible to preserve the "as of date D" information which could be > useful to future readers of the record. The interval nature of the record > would be preserved for the future and would be protected from being > reduced to a (semantically) non-interval "date of first publication". > > A similar reasoning could be applied to permissions as they are expressed > in the quote above. > > Information of when the whole post was last updated may not be useful > enough, since other records in the post may have been updated later. > > I'm aware that the terms "record", "post" and "field" are not always used > consistently, but I assume that you understand my point. > > Regards! > > [UTF-8?]Saašha, -- Edward C. Zimmermann, NONMONOTONIC LAB Basis Systeme netzwerk, Munich Ges. des buergerl. Rechts http://www.nonmonotonic.net Umsatz-St-ID: DE130492967