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hardDatabricksPalantirMicrosoft

Your Spark join is skewed, 199 tasks finish in seconds, one runs for an hour. Fix it.

The Databricks signature deep-dive. Everyone says 'salting', almost nobody can write the salt correctly or explain why AQE might make hand-salting unnecessary. The full playbook, in the order a senior engineer actually tries it.

Updated Sep 2026 · Grounded in real Forward Deployed Engineer interview loops and written to a senior-engineer editorial bar.

The Databricks signature deep-dive. Everyone says 'salting', almost nobody can write the salt correctly or explain why AQE might make hand-salting unnecessary. The full playbook, in the order a senior engineer actually tries it.

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