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Archives & Special Collections

CONTENTdm Cookbook: Valid Date

8a. Valid Date

This field is optional.

sample of elements that show on each field page
Repeatable No
Field Name Valid Date
DC Mapping Date.valid
Search No
Hide No
Vocabulary No
Definition Date (often a range) of validity of a resource.

Use when access to a digital resource is of a limited duration (as in electronic course reserves) or embargoed (as for a chapter of a dissertation that will be published).


Follow W3C-DTF standard (ISO 8601) of YYYY-MM-DD.

Use only as much of the date as is known.

  • If only the month and year is known, use YYYY-MM.
  • If only the year is known, use YYYY.

Use a question mark to show a date is approximate or a circa date.

Use dashes to indicate uncertainty within a decade or a century.

  • YYY-?
  • YY--?

Do not use "Unknown"--just leave the field blank.

For a range of dates, put a dash in between dates.

2006-08-21 - 2006-12-12

Template Yes. If all items in a collection have the same valid dates, use the Template Creator to input the data once for all records.
Nickname N/a (don’t yet have any in the system)

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