Page History

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• in the MARC record, field 300 is the physical description, and subfield "a" contains the page numbers or leaves (note that the "300" field and the "a" subfield are both repeatable in a record). See Marc21 format for bibliographic data for details.
• The "folio_derived.instance_physical_descriptions" derived table is created from the instance physical descriptions array, but shows the entire 300 field, without subfield indicators. See derivation code for this table. (Note that instance records that do not have a physical descriptions array will not be in the derived table.)
• NOTE: Some electronic resources have a 300 field showing page numbers, if the original form of the work was print material

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The example below shows an online resource with "236 pages

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." If your query is only pulling items from a physical location, you should not get any electronic resources. However, it is good to be aware that electronic resources may have physical descritptions inherited from the

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source material. 

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Note that physical descriptions may be entered in many different ways and have a high degree of complexity; parsing out the page count through a regular expression (the methods used here) will never be completely accurate.

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It is impossible to account for every variation of page number entry in your query

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Code to extract the physical description using derived tables

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