marc_export generates empty 852 $a subfields

[Dan Scott]

* Evergreen master (but exists prior)

Problem: 852 $a is supposed to correspond to the institution holding the item from which access is given, according to the MARC Format for Holdings Data specification. As the org unit shortnames typically don't correspond to one of the MARC Code List for Organization entries, we've assumed in the marc_export script that users will define the --location parameter; however, if that parameter isn't defined, the empty string is used and an empty subfield is generated. This, in turn, makes other MARC-parsing tools unhappy. So, only generate an 852 $a if we have an actual value for the --location parameter.

Also, insert the 852 fields in grouped fashion (that is, before any 9xx fields) rather than appending them to the end of the record.

Also, specify the 852 in quotes, and make the ind2 a space - MARC::Record handles it for us anyway, but might as well be clean in case there are type-handling regressions in the future in MARC::Record.

Branch is in working repo at user/dbs/marc_export_fix_location

[Mike Rylander (mrylander)]

Merged to master for great justice.