NAME 1 (replacer)
NAME 2


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1.	What are the distinct values of the availability field in the velov_geo collection ? 

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2.	Provide the average number of available bikes in the commune that has the more velov_stations. 



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3.	Collection comparison
a.	Download the GeoJSON dataset with the actual velo’V station situation from the following page : https://data.grandlyon.com/portail/fr/jeux-de-donnees/stations-velo-v-metropole-lyon-disponibilites-temps-reel/telechargements . Import it in the same database, in the velov2026 collection!

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b.	Count the number of velov stations in the new collection

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c.	Retrieve the list of communes (with no reprtitions)

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d.	Provide a MongoDB query that verifies wether there are velov stations with their "total_stands.capacity" different from "main_stands:capacity". Provide the count of such stations.

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e.	We want to study the differences between the collections velov2026 and velov_geo.  Study the data and propose mongodb solutions to list the stations that are in common, and the stations that are only present in one of the two collections, not using their geographic coordinates. Optimize your queries as much as possible.
Check your results! 
Describe and explain your approach, provide the mongodb queries and illustrate the results with meaningful and easy to understand examples. Provide statistics as well (number of stations in the different categories).

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4 Data enrichment 

a)	Provide the URL that allows you to download the data and explain how you think it can complement the MongoDB collection of Vélo’V stations.






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b)	Download the data and import it into MongoDB, simplify it to have more than one document. Describe your procedure.





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c) 	Provide at least 3 MongoDB queries that combine your new collection with the velov_geo collection using the $lookup operator
Describe your method. Provide: query, results and explanation.Describe your method. Provide: query, results and explanation. 


c.1 first query that involves address comparison (properties.address, properties.nom, … check the fields) 

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c.2 second query that implies geographic coordinate comparison. Create indexes if necessary.

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c.3 for the additional query use your imagination 




