The fixed fields (also called coded fields) are named this because the information allowed to be entered in them is fixed in length and possible options. These fields are used by the computer to limit, qualify, or narrow searches so that it does not retrieve too many records for the patron. However, the patron never sees these codes.
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Type – This field indicates the type of item being described. For books, journals, conference proceedings, etc. it should be coded a.
BLvl – This field indicates the bibliographic level of the item. For monographic items (items that are not serials) it should be coded m.
Desc – This field indicates which cataloging rules were used in creating this record. If the record is cataloged according to AACR2 rules, the field should be coded a, if the record is cataloged according to RDA rules, the field should be coded i.
Cont – This field indicates the nature of the contents. The various codes indicate whether or not certain types of materials are contained in the item. For example:
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Dtst – This field indicates the date/publication status of an item. Most books have a code of s meaning a single date of publication or copyright. But, occasionally, with AACR2 records AND particularly with RDA records there will likely be more than one date. These are the most frequently found codes to use when copy cataloging new materials.
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Ctry – This field indicates the country (and for the United States the State) in which the item was published or produced. Materials published in the U.S. are identified by a 3 letter code (2 letters for the postal code with a “u” at the end. (Ex. )
utu = published in Utah
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cau = published in California