Skip to content
Kharita Challenges

Problems

Real geospatial problems, graded automatically. Choose a track, a level and what you want to hand in.

1 of 59 problems

Pick one for me
Track
Spatial Analysis1 problemPostGIS / SQL3 problemsPython0 problemsRemote Sensing0 problemsCartography0 problemsWeb GIS0 problemsData Management1 problemGIS Architecture0 problems
Level
Beginner1 problemIntermediate2 problemsAdvanced4 problemsExpert0 problems
Hand in
SQL1 problemPython1 problemGeoJSON3 problemsAnswers0 problemsSchema0 problemsDecisions0 problemsDataset file1 problem
Category
Data preparation0 problemsData quality0 problemsSpatial analysis1 problemRaster analysis0 problemsCartography0 problemsDecision support0 problemsGeospatial systems0 problemsWeb delivery0 problems
Sign in to track progress
Spatial AnalysisBeginnerSQLClear all
  1. Not started, Docks and bikes per borough, in one querySpatial analysisSQL

    A point-in-polygon join with GROUP BY — and the outer join that keeps the boroughs with nothing to count.

    PostGIS / SQLbeginnerDifficulty: beginner150 XP~25 min4 checks

    You hand in a spatial SQL query.

    Datasets

    • London boroughs · Polygon · 33 features · EPSG:4326
    • Santander Cycles docking stations (live snapshot) · Point · 799 features · EPSG:4326

    What you’ll do

    • Join stations to boroughs with a spatial predicate
    • Aggregate per borough
    • Keep every borough, including the ones outside the scheme
    ST_ContainsGROUP BYouter jointransportLondonAlso trains Spatial Analysis
    Open problem