Redis medium
How does Redis implement Geospatial commands (e.g., `GEOADD`, `GEODIST`) using its existing architectural components?
- A It implements a custom high-performance Quadtree engine that runs on a dedicated background thread.
- B It leverages an R-Tree index that is physically stored inside the global string-based keyspace segment.
- C It encodes coordinates into a 'Geohash' integer stored in a standard Sorted Set (ZSET).
- D It makes external API calls to geospatial cloud providers to calculate distances between user keys.
Answer: C. It encodes coordinates into a 'Geohash' integer stored in a standard Sorted Set (ZSET).
By turning 2D Latitude/Longitude into a 1D number (Geohash), Redis can reuse its powerful Sorted Set logic. Range queries (find user within 5km) become simple range scans on the ZSET.
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