properly handles no results being returned

minerva.py

@@ -66,6 +66,7 @@ class Query:
             # Because we're using `UNLOAD`, we get a manifest of the files
             # that make up our data.
             files   = self.manifest(tiedot).strip().split("\n")
+            files   = [f.strip() for f in files if f.strip()] # filter empty
 
             # TODO parallelize this
             local   = [self.handler.download(f) for f in files]

test.py

@@ -4,12 +4,19 @@ import pprint
 pp = pprint.PrettyPrinter(indent=4)
 
 athena = m.Athena("hay", "s3://haystac-pmo-athena/")
-query  = athena.query('select * from "trajectories"."kitware" limit 10')
+query  = athena.query(
+"""SELECT *
+FROM trajectories.kitware
+WHERE ST_Disjoint(
+  ST_GeometryFromText('POLYGON((103.6 1.2151693, 103.6 1.5151693, 104.14797 1.5151693, 104.14797 1.2151693, 103.6 1.2151693))'),
+  ST_Point(longitude, latitude)
+)
+""")
 data   = query.results()
 print(data.head(10))
 
 # Everything *needs* to have a column in order for parquet to work, so scalar
 # values have to be assigned something, so here we use `as count` to create
 # a temporary column called `count`
-print(athena.query("select count(*) as count from trajectories.kitware").results().head(1))
+#print(athena.query("select count(*) as count from trajectories.kitware").results().head(1))