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   to you under the Apache License, Version 2.0 (the
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   specific language governing permissions and limitations
   under the License. :)

(:
XQuery Join Query
-------------------
Find the highest recorded temperature (TMAX) for each station for each day over the year 2000.
:)
fn:count(
    let $station_collection := "/tmp/1.0_partition_ghcnd_all_xml/stations"
    for $s in collection($station_collection)
    for $station in $s("stationCollection")("station")
    let $sensor_collection := "/tmp/1.0_partition_ghcnd_all_xml/sensors"
    for $r in collection($sensor_collection)
    for $data in $r("dataCollection")("data")
    where $station("id") eq $data("station")
        and $data("dataType") eq "TMAX" 
        and fn:year-from-dateTime(xs:dateTime(fn:data($data("date")))) eq 2000
    return $data
)