(:
   OBSOLETED!
   date:   22-June-2010
   author: Gary Lewis
   notes:  This program was replaced by count_distinct_unitids_all_years_v2.xq, which
           uses the directory data files themselves instead of distinct_unitids_by_year.xml
           for each year in the times series. We're giving up performance (distinct_unitids_by_year.xml
           files are much smaller), but eliminating the need for the 25 distinct_unitids_by_year.xml files.
           For more detail see count_distinct_unitids_all_years_v2.xq.
:)

(:
   file:    count_distinct_unitids_all_years.xq
   date:    20-May-2010 07:23am GMT-03:00
   author:  Program created by gen_xq_distinct_unitids_all_years.xq
   purpose: Provides a distinct count of institutions in the 25 years of IPEDS directory data files
   usage:   Run this program from its path location.
            Provide the external variable with the path relative to this program location.
   example: zorba -e xml_ipedsFiles:="../xml/metadata/ipedsFiles.xml" -f -q count_distinct_unitids_all_years.xq -z indent=yes
:)

<results>
{
let $x := distinct-values((
fn:doc("../2008/HD2008/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../2007/HD2007/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../2006/HD2006/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../2005/HD2005/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../2004/HD2004/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../2003/HD2003/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../2002/HD2002/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../2001/FA2001HD/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../2000/FA2000HD/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../1998/IC98hdac/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../1997/ic9798_HDR/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../1996/ic9697_A/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../1995/ic9596_A/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../1994/IC1994_A/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../1993/IC1993_A/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../1992/IC1992_A/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../1991/IC1991_hdr/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../1990/IC90HD/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../1989/IC1989_A/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../1988/IC1988_A/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../1987/IC1987_A/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../1986/IC1986_A/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../1985/IC1985/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../1984/IC1984/distinct_unitids_by_year.xml")/directory/inst/@unitid,
fn:doc("../1980/IC1980/distinct_unitids_by_year.xml")/directory/inst/@unitid
))
return count($x)
}
</results>