Distributed Database Question Bank with Answers 09

Question:

List three situations in which adaptive query processing is beneficial.

Answer:

What is adaptive query processing?

Adaptive Query Processing (AQP) analyzes actual query run time statistics and uses that information for subsequent optimizations. It focuses on using runtime feed-back to modify query processing in a way that provides better response time or more efficient CPU utilization.

AQP addresses the problems of missing statistics, unexpected correlations, unpredictable costs, and dynamic data by using feedback to tune execution. 

Situations in which AQP is beneficial:

• In situations where statistics are inaccurate or unavailable – e.g., query processing over a remotely stored web site.

• In situations where statistics change over the lifetime of the query – either because the query is long running (e.g., continuous) or stats are volatile.

• In situations with variable or unpredictable resources e.g., query processing on a cluster of shared machines

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What is adaptive query processing

When adaptive query processing is beneficial in ddb

What are the situations in which adaptive query processing is beneficial