Indexing and Query Optimization

Description: This quiz will test your knowledge on indexing and query optimization techniques used in geographical data warehousing.
Number of Questions: 15
Created by:
Tags: indexing query optimization geographical data warehousing
Attempted 0/15 Correct 0 Score 0

Which of the following is not a type of index used in geographical data warehousing?

  1. Spatial Index

  2. Temporal Index

  3. Attribute Index

  4. Inverted Index


Correct Option: D
Explanation:

Inverted indexes are typically used in text-based data warehousing, not geographical data warehousing.

What is the purpose of a spatial index in geographical data warehousing?

  1. To improve the performance of spatial queries

  2. To reduce the size of the data warehouse

  3. To improve the accuracy of spatial data

  4. To make the data warehouse more scalable


Correct Option: A
Explanation:

Spatial indexes are used to speed up the processing of spatial queries, such as finding all the features within a given region or finding the nearest feature to a given point.

Which of the following is not a type of spatial index?

  1. R-tree

  2. Quadtree

  3. K-d tree

  4. B-tree


Correct Option: D
Explanation:

B-trees are not spatial indexes. They are a type of balanced search tree used for indexing data in a relational database.

What is the purpose of a temporal index in geographical data warehousing?

  1. To improve the performance of temporal queries

  2. To reduce the size of the data warehouse

  3. To improve the accuracy of temporal data

  4. To make the data warehouse more scalable


Correct Option: A
Explanation:

Temporal indexes are used to speed up the processing of temporal queries, such as finding all the features that changed within a given time period or finding the state of a feature at a given time.

Which of the following is not a type of temporal index?

  1. Interval tree

  2. Timestamp index

  3. B-tree

  4. Allen algebra index


Correct Option: C
Explanation:

B-trees are not temporal indexes. They are a type of balanced search tree used for indexing data in a relational database.

What is the purpose of an attribute index in geographical data warehousing?

  1. To improve the performance of attribute queries

  2. To reduce the size of the data warehouse

  3. To improve the accuracy of attribute data

  4. To make the data warehouse more scalable


Correct Option: A
Explanation:

Attribute indexes are used to speed up the processing of attribute queries, such as finding all the features with a given attribute value or finding the maximum value of an attribute.

Which of the following is not a type of attribute index?

  1. Hash index

  2. Bitmap index

  3. B-tree

  4. R-tree


Correct Option: D
Explanation:

R-trees are not attribute indexes. They are a type of spatial index used for indexing data in a geographical data warehouse.

What is the purpose of query optimization in geographical data warehousing?

  1. To improve the performance of queries

  2. To reduce the size of the data warehouse

  3. To improve the accuracy of data

  4. To make the data warehouse more scalable


Correct Option: A
Explanation:

Query optimization is the process of improving the performance of queries by using techniques such as indexing, materialized views, and query rewriting.

Which of the following is not a query optimization technique used in geographical data warehousing?

  1. Cost-based optimization

  2. Rule-based optimization

  3. Heuristic-based optimization

  4. Data partitioning


Correct Option: D
Explanation:

Data partitioning is a data management technique, not a query optimization technique.

What is the purpose of cost-based optimization in geographical data warehousing?

  1. To estimate the cost of executing a query

  2. To choose the most efficient execution plan for a query

  3. To improve the accuracy of data

  4. To make the data warehouse more scalable


Correct Option: B
Explanation:

Cost-based optimization uses statistical information about the data and the query to estimate the cost of executing a query. This information is then used to choose the most efficient execution plan for the query.

Which of the following is not a cost-based optimization technique used in geographical data warehousing?

  1. Dynamic programming

  2. Branch and bound

  3. Simulated annealing

  4. Genetic algorithms


Correct Option: C
Explanation:

Simulated annealing is a heuristic-based optimization technique, not a cost-based optimization technique.

What is the purpose of rule-based optimization in geographical data warehousing?

  1. To apply a set of predefined rules to optimize a query

  2. To choose the most efficient execution plan for a query

  3. To improve the accuracy of data

  4. To make the data warehouse more scalable


Correct Option: A
Explanation:

Rule-based optimization applies a set of predefined rules to optimize a query. These rules are typically based on the structure of the query and the characteristics of the data.

Which of the following is not a rule-based optimization technique used in geographical data warehousing?

  1. Predicate pushing

  2. Join reordering

  3. Index selection

  4. Materialized view selection


Correct Option: D
Explanation:

Materialized view selection is a cost-based optimization technique, not a rule-based optimization technique.

What is the purpose of heuristic-based optimization in geographical data warehousing?

  1. To use heuristics to optimize a query

  2. To choose the most efficient execution plan for a query

  3. To improve the accuracy of data

  4. To make the data warehouse more scalable


Correct Option: A
Explanation:

Heuristic-based optimization uses heuristics to optimize a query. Heuristics are rules of thumb that are used to make decisions about how to optimize a query.

Which of the following is not a heuristic-based optimization technique used in geographical data warehousing?

  1. Greedy algorithms

  2. Local search algorithms

  3. Simulated annealing

  4. Genetic algorithms


Correct Option: C
Explanation:

Simulated annealing is a cost-based optimization technique, not a heuristic-based optimization technique.

- Hide questions