agriculture-report.taq

$ java -jar taq.jar agriculture-report ^do_export

Running query do_export in initialize scope 
Parameters [agriculture-report, ^do_export]

$ java -jar taq.jar ^agriculture-report

Running query more_agriculture in global scope 
Parameters [agriculture-report, ^agriculture-report]

Description

agriculture-report.taq demonstrates two highly customized database resource providers. The ‘more_agriculture’ query produces a list of countries which have increased the area under agriculture by more than 1% over the twenty years between 1990 and 2010. The database records are revealed by a separate “show-agri20-year1” program using a custom SQL resource provider.

$ java -jar taq.jar show-agri20-year1

Running query show_more_agriculture in global scope 

Country, area and percent area under agriculture data points:

1   Afghanistan,652230.0,58.3,58.3,58.3,57.9,58.1
2   Albania,28750.0,45.1,40.8,40.5,41.8,43.9
...
207 Zambia,752610.0,26.6,26.6,28.1,30.1,31.5
208 Zimbabwe,390760.0,30.2,31.6,33.5,38.4,42.4

Country, area and increased surface area in square km:

1   Albania,986.1,
2   Algeria,25722.8,
...
64  Zambia,25212.4,
65  Zimbabwe,34777.6,

resource agri_area_percent
(
database="db/agri-area-percent1",
type="H2"
)
{
"agriculture.AgriAreaPercent" -> axiom agri_area_percent()
axiom agri_decades() -> "agriculture.AgriAreaPercent"
}

resource surface_area_increase: "agri_20_year"
(
database="db/agri_20_year1",
type="H2"
)
{ template surface_area_increase -> "agriculture.Agri20Year" }
(
surface_area_increase.drop_tables()
)

flow surface_area_increase
(
. double agri_change = Y2010 - Y1990,
country ? agri_change > 1.0,
double surface_area = agri_change/100.0 * surface_area_Km2
)

query more_agriculture(agri_area_percent : surface_area_increase)

scope initialize
{
include "agri-decades.taq"

flow agri_export
{ cursor record(agri_decades) }
(
agri_area_percent.drop_tables(),
{ ?? (item = record++) agri_area_percent.emit(item) }
)

query do_export(agri_export)
}