Minor cleanup.

population.py

@@ -52,7 +52,6 @@ def init_db(conn):
             'insert into populations(species, home_star, pop, planet) values (?, ?, ?, ?)',
             (people_name, home_star_id, INITIAL_POP, planet_id),
         )
-        # print(planet_id, bio, industrial_capacity)
     c.close()
     conn.commit()
 

server.py

@@ -59,7 +59,7 @@ def life_grows(db_cursor):
         else:
             excess_bio = 0
 
-        bio = bio + new_bio
+        bio += new_bio
         assert bio <= bio_capacity
         print(
             f'setting planet {planet_id} bio to {bio} increment of {new_bio}, excess_bio {excess_bio}'

stars.py

@@ -72,11 +72,7 @@ def init_db(conn):
     print('Generating star data.')
     c = conn.cursor()
     for values in generate_stars(WIDTH, HEIGHT, MINIMUM_DISTANCE_BETWEEN_STARS):
-        try:
-            c.execute('insert into stars(x, y, radius, name) values (?, ?, ?, ?)', values)
-        except sqlite3.IntegrityError:
-            print(values)  # "Rubbpo"
-            continue
+        c.execute('insert into stars(x, y, radius, name) values (?, ?, ?, ?)', values)
         generate_planets_for_star(c)
     c.close()
     conn.commit()
@@ -91,39 +87,21 @@ def iter_stars(conn):
 
 def get_planets_for_star_named(conn, name):
     c = conn.cursor()
-    c.execute('select id from stars where "name" = ?', (name,))
-    (star_id,) = c.fetchone()
     c.execute(
-        'select ordo, bio_capacity, industrial_capacity from planets'
-        ' where "star" = ?'
-        ' order by ordo'
-        ' limit 29',  # Because we only have 29 Roman numbers.
-        (star_id,),
-    )
-    # Note that fetchone() returns a tuple value suitable for passing
-    # to execute() as the values tuple.  I destructure the result tuple
-    # and build a new one soley because it would be slightly obscure to
-    # do otherwise.  I might use a variable named, say, star_id_tuple or
-    # star_id_row and pass it directly to execute(), or even go full
-    # cowboy and put the call to fetchone() in the parameter position in
-    # the call to execute() and eschew a variable altogether.  But if
-    # somehow the query is made for a star name that isn't in the DB then
-    # the traceback would be unnecessarily unclear.
-    #
-    # In the event, having gone to this length to explain the situation
-    # I'll probably come back and switch to reusing the result tuple.
-    # I hate the waste.  I bet if you looked at the bytecode the work is
-    # there: unpacking and repacking the id int.  Bleah.  Then again,
-    # this is running in response to a user event and the extra work is
-    # done once and it's not a lot compared to all the other work that's
-    # about to happen (drawing these planet data into the GUI) so it
-    # would be daft to worry about it (after working this all out, that
-    # is.)
-    #
-    # Now that I can do JOIN's I could write a mighty SQL statement that
-    # did all the work in the DB!  I could be like the old programmers of
-    # yore!
-
+        '''\
+        select
+            planets.ordo,
+            planets.bio_capacity,
+            planets.industrial_capacity
+        from planets join stars
+        on stars.id = planets.star
+        and stars.name = ?
+        order by planets.ordo
+        limit 29
+        ''',  # Limit because we only have 29 Roman numbers.
+        (name,)
+        )
+    # TODO: move the display-related code to ui module?
     for ordo, bio_capacity, industrial_capacity in c.fetchall():
         assert bio_capacity >= 0
         assert industrial_capacity >= 0