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UID:pretalx-pycon-portugal-2026-GU9KWG@pretalx.evolutio.pt
DTSTART:20260903T140000Z
DTEND:20260903T143000Z
DESCRIPTION:Have you ever looked at a PySpark pipeline and assumed it would
  run top-to-bottom? You’d be surprised…it doesn’t. In reality\, Spar
 k builds and optimizes execution plans\, and this mismatch can lead to sub
 tle\, production-grade bugs.\nIn this talk\, I’ll walk through a real-wo
 rld example where reading and updating the same tables produced inconsiste
 nt results in production. We’ll see why this happens\, what Spark actual
 ly executes under the hood\, and why code that looks correct can behave un
 expectedly.\nJoin this session and you’ll learn practical design princip
 les to make pipelines predictable: introducing explicit materializations\,
  using declarative patterns\, or imposing physical separation between sour
 ces and targets.
DTSTAMP:20260819T143235Z
LOCATION:Auditorium
SUMMARY:The illusion of sequential execution in PySpark - Pier Paolo La Pas
 tina
URL:https://pretalx.evolutio.pt/pycon-portugal-2026/talk/GU9KWG/
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