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UID:pretalx-sotm2026-CXXRXD@pretalx.com
DTSTART;TZID=CET:20260828T164500
DTEND;TZID=CET:20260828T170500
DESCRIPTION:SNCF Transilien has mapped with great details 436 train station
 s in the Greater Paris area. This work was conducted in several stages\, b
 etween 2018 and 2022. An application using this data helps travelers to fi
 nd their way inside and around railway stations. The app displays multi-le
 vel floor plans\, enables users to find equipments and services\, and prov
 ides indoor/outdoor routing with an option to use elevators rather than st
 airways.\n\nEnsuring these services function properly requires to **mainta
 in the data**. This means both updating it when a station or its neighbour
 hood has changed\, and preserving the high quality of the data. The latter
  is achieved by checking changes to the data inside and around railway sta
 tions. This **moderation work** is achieved through an innovative process 
 that enables us to :\n- compare the data for each station between 2 dates 
 freely defined\n- detect and classify changes that need to be checked \n- 
 apply a whitelist to avoid checking one's own changes\n- review those chan
 ges and produce a report \n\nWe set up a project that is based on **PostGI
 S** and **QGIS**\, makes use of **osmium** and **osm2pgsql**\, and require
 s a small amount of SQL code to detect changes. This project enables us to
  efficiently moderate the data changes that can impact the SNCF app. \n\nT
 his talk will present our methodology\, which can be replicated and adapte
 d to all sorts of OSM data\, along with a few helpful tricks.
DTSTAMP:20260609T202711Z
LOCATION:Martinique
SUMMARY:How Carto’Cité maintains OSM data for 436 train stations efficie
 ntly using PostGIS and QGIS - Antoine Riche
URL:https://pretalx.com/sotm2026/talk/CXXRXD/
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