Recall & Review
beginner
What is query optimization in databases?
Query optimization is the process of choosing the most efficient way to execute a database query to reduce resource use and execution time.
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beginner
How does query optimization reduce execution time?
It finds the fastest method to access and process data by selecting better query plans, reducing unnecessary operations.
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beginner
What role do indexes play in query optimization?
Indexes help the database quickly locate data without scanning entire tables, speeding up query execution.
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intermediate
Why is reducing disk I/O important in query optimization?
Disk input/output is slow; minimizing it by efficient data access reduces the time the query takes to run.
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beginner
What is a query execution plan?
A query execution plan is a step-by-step strategy the database uses to run a query efficiently.
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What does query optimization primarily aim to reduce?
✗ Incorrect
Query optimization focuses on reducing the time it takes to run a query.
Which of the following helps speed up data retrieval in query optimization?
✗ Incorrect
Indexes allow faster access to data, improving query speed.
Why is minimizing disk I/O important in query optimization?
✗ Incorrect
Reducing disk input/output speeds up query processing.
What does a query execution plan describe?
✗ Incorrect
It shows the strategy the database uses to execute a query.
Which factor is NOT directly improved by query optimization?
✗ Incorrect
Query optimization improves speed and resource use but does not change the correctness of results.
Explain in your own words why query optimization reduces execution time.
Think about how the database chooses the best way to get data quickly.
You got /4 concepts.
Describe how indexes help in query optimization and execution speed.
Imagine looking up a word in a dictionary using the index.
You got /3 concepts.