def optimized_count(self, **kwargs):
"""Return count in optimized manner
Apple.objects.filter(indice=4).count()
Apple.objects.optimized_count(indice=4)
"""
if (len(kwargs) == 0):
raise MissingKwargs("you must specify the filter clause")
if (len(kwargs) > 1):
raise TooManyKwargs()
# do not care about more than one kwarg
(key, value) = kwargs.items()[0]
(nbe, column, qfilter) = tool.parse_kwarg(key)
agg = 'agg_count'
agf = agg.split('_')
agt = util.AggTrigger(util.PG_BACKEND, self.model._meta.db_table,
column)
if nbe == 1:
agf = agg
elif nbe == 2:
agf = agt.agg_function(agg, agf[1])
cursor = connection.cursor()
qry = """SELECT {} FROM {} WHERE {} %s"""
tbname = util.table_name(self.model._meta.db_table, column)
cursor.execute(qry.format(agf, tbname, qfilter), [value])
row = cursor.fetchone()
return row[0]
def test_less_or_equal_than(self):
res = tool.parse_kwarg("foo__lte")
self.assertEqual(res, (2, 'foo', 'foo <='))
def test_greater_or_equal_than(self):
res = tool.parse_kwarg("foo__gte")
self.assertEqual(res, (2, 'foo', 'foo >='))
def test_equal(self):
res = tool.parse_kwarg("foo")
self.assertEqual(res, (1, 'foo', 'foo='))
def test_less_or_equal_than(self):
res = tool.parse_kwarg("foo__lte")
self.assertEqual(res, (2, 'foo', 'foo <='))
def test_greater_or_equal_than(self):
res = tool.parse_kwarg("foo__gte")
self.assertEqual(res, (2, 'foo', 'foo >='))
def test_equal(self):
res = tool.parse_kwarg("foo")
self.assertEqual(res, (1, 'foo', 'foo='))
