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Q99 / 100
What is "cost-based optimization" (CBO) in a query engine, and what does it rely on?
Correct! Well done.
Incorrect.
The correct answer is A) The optimizer uses collected statistics (row counts, data distributions) to estimate the cost of different execution plans and choose the cheapest one
A
Correct Answer
The optimizer uses collected statistics (row counts, data distributions) to estimate the cost of different execution plans and choose the cheapest one
Explanation
CBO relies on table/column statistics (cardinality, distinct counts, histograms) to estimate costs of alternative plans, e.g., choosing join order or join strategy.
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