Compares two models

In this example we show how to use polaris testing capabilities for comparing two different networks

import shutil
from pathlib import Path

from polaris import Polaris
from polaris.utils.testing.model_comparison.compare_databases import compare_databases
from polaris.utils.testing.temp_model import TempModel


# Let's copy the model we have available for testing
model_path1 = TempModel("Grid")
model_path2 = Path("/tmp/Grid_model_comparison")
if model_path2.exists():
    shutil.rmtree(model_path2)
shutil.copytree(model_path1, "/tmp/Grid_model_comparison")

project1 = Polaris.from_dir(model_path1)
project2 = Polaris.from_dir(model_path2)

⚠️ Friendly exception handler is disabled via FRIENDLY_ERRORS_DISABLED

We can compare two identical supply files We must provide the path to the supply databases

report = compare_databases(project1.supply_file, project2.supply_file)

for record in report:
    print(record)

2026-06-07 10:08:18 UTC+0000 - about_model
2026-06-07 10:08:18 UTC+0000 - area_type
2026-06-07 10:08:18 UTC+0000 - connection
2026-06-07 10:08:18 UTC+0000 - counties
2026-06-07 10:08:18 UTC+0000 - electricity_grid_transmission
2026-06-07 10:08:18 UTC+0000 - electricity_provider
2026-06-07 10:08:18 UTC+0000 - electricity_provider_pricing
2026-06-07 10:08:18 UTC+0000 - ev_charging_station_plug_types
2026-06-07 10:08:18 UTC+0000 - ev_charging_station_plugs
2026-06-07 10:08:18 UTC+0000 - ev_charging_station_pricing
2026-06-07 10:08:18 UTC+0000 - ev_charging_station_service_bays
2026-06-07 10:08:18 UTC+0000 - ev_charging_stations
2026-06-07 10:08:18 UTC+0000 - geo_consistency_controller
2026-06-07 10:08:18 UTC+0000 - land_use
2026-06-07 10:08:18 UTC+0000 - link
2026-06-07 10:08:18 UTC+0000 - link_overrides
2026-06-07 10:08:18 UTC+0000 - link_type
2026-06-07 10:08:18 UTC+0000 - location
2026-06-07 10:08:18 UTC+0000 - location_attributes
2026-06-07 10:08:18 UTC+0000 - location_links
2026-06-07 10:08:18 UTC+0000 - location_parking
2026-06-07 10:08:18 UTC+0000 - micromobility_agencies
2026-06-07 10:08:18 UTC+0000 - micromobility_docks
2026-06-07 10:08:18 UTC+0000 - micromobility_operators
2026-06-07 10:08:18 UTC+0000 - migrations
2026-06-07 10:08:18 UTC+0000 - node
2026-06-07 10:08:18 UTC+0000 - parking
2026-06-07 10:08:18 UTC+0000 - parking_pricing
2026-06-07 10:08:18 UTC+0000 - parking_rule
2026-06-07 10:08:19 UTC+0000 - phasing
2026-06-07 10:08:19 UTC+0000 - phasing_nested_records
2026-06-07 10:08:19 UTC+0000 - pocket
2026-06-07 10:08:19 UTC+0000 - popsyn_region
2026-06-07 10:08:19 UTC+0000 - restricted_lanes
2026-06-07 10:08:19 UTC+0000 - road_connectors
2026-06-07 10:08:19 UTC+0000 - roadsideunit
2026-06-07 10:08:19 UTC+0000 - sanity_check
2026-06-07 10:08:19 UTC+0000 - settings
2026-06-07 10:08:19 UTC+0000 - sign
2026-06-07 10:08:19 UTC+0000 - signal
2026-06-07 10:08:19 UTC+0000 - signal_nested_records
2026-06-07 10:08:19 UTC+0000 - timing
2026-06-07 10:08:19 UTC+0000 - timing_nested_records
2026-06-07 10:08:19 UTC+0000 - toll_pricing
2026-06-07 10:08:19 UTC+0000 - transit_agencies
2026-06-07 10:08:19 UTC+0000 - transit_bike
2026-06-07 10:08:19 UTC+0000 - transit_fare_attributes
2026-06-07 10:08:19 UTC+0000 - transit_fare_rules
2026-06-07 10:08:19 UTC+0000 - transit_links
2026-06-07 10:08:19 UTC+0000 - transit_modes
2026-06-07 10:08:19 UTC+0000 - transit_pattern_links
2026-06-07 10:08:19 UTC+0000 - transit_pattern_mapping
2026-06-07 10:08:19 UTC+0000 - transit_patterns
2026-06-07 10:08:19 UTC+0000 - transit_routes
2026-06-07 10:08:19 UTC+0000 - transit_stops
2026-06-07 10:08:19 UTC+0000 - transit_trips
2026-06-07 10:08:19 UTC+0000 - transit_trips_schedule
2026-06-07 10:08:19 UTC+0000 - transit_walk
2026-06-07 10:08:19 UTC+0000 - transit_zones
2026-06-07 10:08:19 UTC+0000 - turn_overrides
2026-06-07 10:08:19 UTC+0000 - use_code
2026-06-07 10:08:19 UTC+0000 - weather_impact
2026-06-07 10:08:19 UTC+0000 - zone
**No dropped tables**

**No new tables**

**Tables with no changes**:

about_model, area_type, connection, counties, electricity_grid_transmission, electricity_provider, electricity_provider_pricing, ev_charging_station_plug_types, ev_charging_station_plugs, ev_charging_station_pricing, ev_charging_station_service_bays, ev_charging_stations, geo_consistency_controller, land_use, link, link_overrides, link_type, location, location_attributes, location_links, location_parking, micromobility_agencies, micromobility_docks, micromobility_operators, migrations, node, parking, parking_pricing, parking_rule, phasing, phasing_nested_records, pocket, popsyn_region, restricted_lanes, road_connectors, roadsideunit, sanity_check, settings, sign, signal, signal_nested_records, timing, timing_nested_records, toll_pricing, transit_agencies, transit_bike, transit_fare_attributes, transit_fare_rules, transit_links, transit_modes, transit_pattern_links, transit_pattern_mapping, transit_patterns, transit_routes, transit_stops, transit_trips, transit_trips_schedule, transit_walk, transit_zones, turn_overrides, use_code, weather_impact, zone

Or we can do something drastic like remove all transit data and then compare them

project2.network.transit.purge()

report = compare_databases(project1.supply_file, project2.supply_file)

for record in report:
    print(record)

project1.close()
project2.close()

2026-06-07 10:08:20 UTC+0000 - Working with file on /tmp/Grid_model_comparison/Grid-Supply.sqlite
2026-06-07 10:08:20 UTC+0000 - Clearing transit tables
2026-06-07 10:08:20 UTC+0000 - Table "TRANSIT_RAW_SHAPES" does not exist in the network
2026-06-07 10:08:21 UTC+0000 - about_model
2026-06-07 10:08:21 UTC+0000 - area_type
2026-06-07 10:08:21 UTC+0000 - connection
2026-06-07 10:08:21 UTC+0000 - counties
2026-06-07 10:08:21 UTC+0000 - electricity_grid_transmission
2026-06-07 10:08:21 UTC+0000 - electricity_provider
2026-06-07 10:08:21 UTC+0000 - electricity_provider_pricing
2026-06-07 10:08:21 UTC+0000 - ev_charging_station_plug_types
2026-06-07 10:08:21 UTC+0000 - ev_charging_station_plugs
2026-06-07 10:08:21 UTC+0000 - ev_charging_station_pricing
2026-06-07 10:08:21 UTC+0000 - ev_charging_station_service_bays
2026-06-07 10:08:21 UTC+0000 - ev_charging_stations
2026-06-07 10:08:21 UTC+0000 - geo_consistency_controller
2026-06-07 10:08:21 UTC+0000 - land_use
2026-06-07 10:08:21 UTC+0000 - link
2026-06-07 10:08:21 UTC+0000 - link_overrides
2026-06-07 10:08:21 UTC+0000 - link_type
2026-06-07 10:08:21 UTC+0000 - location
2026-06-07 10:08:21 UTC+0000 - location_attributes
2026-06-07 10:08:21 UTC+0000 - location_links
2026-06-07 10:08:21 UTC+0000 - location_parking
2026-06-07 10:08:21 UTC+0000 - micromobility_agencies
2026-06-07 10:08:21 UTC+0000 - micromobility_docks
2026-06-07 10:08:21 UTC+0000 - micromobility_operators
2026-06-07 10:08:21 UTC+0000 - migrations
2026-06-07 10:08:21 UTC+0000 - node
2026-06-07 10:08:21 UTC+0000 - parking
2026-06-07 10:08:21 UTC+0000 - parking_pricing
2026-06-07 10:08:21 UTC+0000 - parking_rule
2026-06-07 10:08:21 UTC+0000 - phasing
2026-06-07 10:08:21 UTC+0000 - phasing_nested_records
2026-06-07 10:08:21 UTC+0000 - pocket
2026-06-07 10:08:21 UTC+0000 - popsyn_region
2026-06-07 10:08:21 UTC+0000 - restricted_lanes
2026-06-07 10:08:21 UTC+0000 - road_connectors
2026-06-07 10:08:21 UTC+0000 - roadsideunit
2026-06-07 10:08:21 UTC+0000 - sanity_check
2026-06-07 10:08:21 UTC+0000 - settings
2026-06-07 10:08:21 UTC+0000 - sign
2026-06-07 10:08:21 UTC+0000 - signal
2026-06-07 10:08:21 UTC+0000 - signal_nested_records
2026-06-07 10:08:21 UTC+0000 - timing
2026-06-07 10:08:21 UTC+0000 - timing_nested_records
2026-06-07 10:08:21 UTC+0000 - toll_pricing
2026-06-07 10:08:21 UTC+0000 - transit_agencies
2026-06-07 10:08:21 UTC+0000 - transit_bike
2026-06-07 10:08:21 UTC+0000 - transit_fare_attributes
2026-06-07 10:08:22 UTC+0000 - transit_fare_rules
2026-06-07 10:08:22 UTC+0000 - transit_links
2026-06-07 10:08:22 UTC+0000 - transit_modes
2026-06-07 10:08:22 UTC+0000 - transit_pattern_links
2026-06-07 10:08:22 UTC+0000 - transit_pattern_mapping
2026-06-07 10:08:22 UTC+0000 - transit_patterns
2026-06-07 10:08:22 UTC+0000 - transit_routes
2026-06-07 10:08:22 UTC+0000 - transit_stops
2026-06-07 10:08:22 UTC+0000 - transit_trips
2026-06-07 10:08:22 UTC+0000 - transit_trips_schedule
2026-06-07 10:08:22 UTC+0000 - transit_walk
2026-06-07 10:08:22 UTC+0000 - transit_zones
2026-06-07 10:08:22 UTC+0000 - turn_overrides
2026-06-07 10:08:22 UTC+0000 - use_code
2026-06-07 10:08:22 UTC+0000 - weather_impact
2026-06-07 10:08:22 UTC+0000 - zone
**No dropped tables**

**No new tables**

**Tables with no changes**:

about_model, area_type, connection, counties, electricity_grid_transmission, electricity_provider, electricity_provider_pricing, ev_charging_station_plug_types, ev_charging_station_plugs, ev_charging_station_pricing, ev_charging_station_service_bays, ev_charging_stations, land_use, link, link_overrides, link_type, location, location_attributes, location_links, location_parking, micromobility_agencies, micromobility_docks, micromobility_operators, migrations, node, parking, parking_pricing, parking_rule, phasing, phasing_nested_records, pocket, popsyn_region, restricted_lanes, road_connectors, roadsideunit, sanity_check, settings, sign, signal, signal_nested_records, timing, timing_nested_records, toll_pricing, transit_modes, transit_pattern_mapping, turn_overrides, use_code, weather_impact, zone



**Tables with changes**:

geo_consistency_controller:

     * 2 records added to table

transit_agencies:

     * 7 records deleted from table

transit_bike:

     * 530 records deleted from table

transit_fare_attributes:

     * 6 records deleted from table

transit_fare_rules:

     * 18 records deleted from table

transit_links:

     * 46 records deleted from table

transit_pattern_links:

     * 46 records deleted from table

transit_patterns:

     * 15 records deleted from table

transit_routes:

     * 6 records deleted from table

transit_stops:

     * 38 records deleted from table

transit_trips:

     * 3,923 records deleted from table

transit_trips_schedule:

     * 16,743 records deleted from table

transit_walk:

     * 530 records deleted from table

transit_zones:

     * 6 records deleted from table