Faster ogn range calculation

ogn/collect/ognrange.py

@@ -3,6 +3,7 @@ from celery.utils.log import get_task_logger
 from sqlalchemy import String
 from sqlalchemy import and_, insert, update, exists, between
 from sqlalchemy.sql import func, null
+from sqlalchemy.sql.expression import literal_column
 
 from ogn.collect.celery import app
 from ogn.model import AircraftBeacon, ReceiverCoverage
@@ -29,7 +30,6 @@ def create_receiver_coverage(session=None, date=None):
     # Filter aircraft beacons and shrink precision of MGRS from 1m to 1km resolution: 30UXC 00061 18429 -> 30UXC 00 18
     sq = session.query((func.left(AircraftBeacon.location_mgrs, 5, type_=String) + func.substring(AircraftBeacon.location_mgrs, 6, 2, type_=String) + func.substring(AircraftBeacon.location_mgrs, 11, 2, type_=String)).label('reduced_mgrs'),
                        AircraftBeacon.receiver_id,
-                       func.date(AircraftBeacon.timestamp).label('date'),
                        AircraftBeacon.signal_quality,
                        AircraftBeacon.altitude,
                        AircraftBeacon.device_id) \
@@ -42,15 +42,14 @@ def create_receiver_coverage(session=None, date=None):
     # ... and group them by reduced MGRS, receiver and date
     query = session.query(sq.c.reduced_mgrs,
                           sq.c.receiver_id,
-                          sq.c.date,
+                          literal_column("'{}'".format(date.strftime('%Y-%m-%d'))).label('date'),
                           func.max(sq.c.signal_quality).label('max_signal_quality'),
                           func.min(sq.c.altitude).label('min_altitude'),
                           func.max(sq.c.altitude).label('max_altitude'),
                           func.count(sq.c.altitude).label('aircraft_beacon_count'),
                           func.count(func.distinct(sq.c.device_id)).label('device_count')) \
         .group_by(sq.c.reduced_mgrs,
-                  sq.c.receiver_id,
+                  sq.c.receiver_id) \
-                  sq.c.date) \
         .subquery()
 
     # if a receiver coverage entry exist --> update it

ogn/model/receiver_coverage.py

@@ -1,5 +1,6 @@
-from sqlalchemy import Column, String, Integer, SmallInteger, Float, Date, ForeignKey
+from sqlalchemy import Column, String, Integer, SmallInteger, Float, Date, ForeignKey, Index
 from sqlalchemy.orm import relationship, backref
+from sqlalchemy.sql import func
 
 
 from .base import Base
@@ -21,3 +22,7 @@ class ReceiverCoverage(Base):
     # Relations
     receiver_id = Column(Integer, ForeignKey('receivers.id', ondelete='SET NULL'), primary_key=True)
     receiver = relationship('Receiver', foreign_keys=[receiver_id], backref=backref('receiver_coverages', order_by='ReceiverCoverage.date.asc()'))
+
+
+Index('ix_receiver_coverages_date_receiver_id', ReceiverCoverage.date, ReceiverCoverage.receiver_id)
+Index('ix_receiver_coverages_receiver_id_date', ReceiverCoverage.receiver_id, ReceiverCoverage.date)