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Cassandra hard

A developer runs `DELETE FROM table WHERE id = 1 AND timestamp < yesterday`. This creates a 'Range Tombstone'. Why can this cause subsequent `SELECT` queries for `id = 1` to fail with a timeout?

  1. A Because range tombstones permanently lock the table until the next full moon.
  2. B Scanning Complexity: The read path must merge the Range Tombstone from multiple SSTables. If there are many overlapping range tombstones, the database must perform complex 'Interval Tree' logic at read-time, consuming massive CPU/Heap.
  3. C Range tombstones are stored in the Cloud and require a network timeout to fetch.
  4. D It is not possible; range deletes are the fastest way to remove data.

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