CS4482tut5a - o Cost of indexed nested loop join of the...

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CS4482/6492 Advanced Database Systems Tutorial 5 1. a) Salary > 55,000 ( ENGINEER ID=ICEngID PROJECT ) b) ( Salary > 55,000 ( ENGINEER )) ID=ICEngID PROJECT c) Option 1 (not the cheapest): o Number of tuples satisfying the selection condition = 10000 * (60,000- 55,000)/(60,000-10,000) = 1,000 o Cost of selection = 2 + 1000 = 1002 o Pipeline the selection output to the join operator.
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Unformatted text preview: o Cost of indexed nested loop join of the output of selection and PROJECT = 1000 * (2+1) = 3,000 o Total cost = 1002 + 3000 = 4002 2. a) at most 1000 tuples. b) approximately 10,227 tuples ENGINNER Salary>55000 (use index on Salary) PROJECT ID=ICEngID (use index on ICEngID) pipeline...
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