What is COST-based approach to optimization ?
Answers were Sorted based on User's Feedback
Answer / mahesh
For running any quey requires or generates an execution pan
before actually fetching data
in cost based approach, the oracle will generates the
execution plan based on available statistics.
oracle supports cost based approcach and it is continuously
improving fron one version to another version of oralce
database
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Answer / mkjmkumar
Oracle Analyse a Query using two Approches
1. CBO
2. RBO
Cost Based Analyser is default when we do not in oracle
setup.
CBO picks up query output using witch have less cost
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Answer / tony
Cost Based Optimizer (CBO) - This method is used if
internal statistics are present. The CBO checks several
possible execution plans and selects the one with the
lowest cost, where cost relates to system resources.
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Answer / mkjmkumar
CBO Evaluates the cost of available execution paths and
selects the execution path that has lowest relative cost.
Is This Answer Correct ? | 1 Yes | 1 No |
Answer / nishi
oracle generate the execution plan to the available statistics.
Is This Answer Correct ? | 0 Yes | 0 No |
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