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Reading an execution plan end to end

unwritten—Outline
Note to self
Not written yet. This is the outline I am working from — it will be filled in as I go through the topic.
  • Reading a plan right to left, inside out
  • Operator costs: seek, scan, key lookup, nested loops, hash match
  • Estimated vs actual rows and where the estimate went wrong
  • Warnings worth acting on: spills, implicit conversions, missing indexes
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How the optimizer picks an index
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Isolation levels and what each one actually prevents