Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 15: Problem 7

What is meant by cost-based query optimization?

Short Answer

Expert verified
Cost-based query optimization is a technique used in DBMS where the database optimizer chooses the most efficient execution plan for an SQL query based on the cost, which is estimated based on system resources like I/O operations, communication cost etc. The plan with the least cost is chosen.

Step by step solution

01

Defining Cost-Based Query Optimization

Cost-based query optimization is a method used in databases to optimize the execution of SQL queries. The DBMS's role here is to find the most efficient way to execute the received SQL queries.
02

Explaining the Process

In this strategy, various query execution plans are generated with different combinations and each plan's cost is estimated. The cost here represents the amount of system resources used such as I/O operations, communication cost, etc. The database optimizer chooses the plan with the least cost.
03

Disclosing the Benefits

This approach provides significant benefits. It allows the database system to adapt to the current environment and resource availability, and choose the plan that completes in the least amount of time.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

What is meant by the term heuristic optimization? Discuss the main heuristics that are applied during query optimization.

What is meant by semantic query optimization? How does it differ from other query optimization techniques?

A file of 4096 blocks is to be sorted with an available buffer space of 64 blocks. How many passes will be needed in the merge phase of the external sort-merge algorithm?

Discuss the cost components for a cost function that is used to estimate query execution cost. Which cost components are used most often as the basis for cost functions?

Discuss the different types of parameters that are used in cost functions. Where is this information kept?
See all solutions

Recommended explanations on Computer Science Textbooks

Computer Programming

Read Explanation

Game Design in Computer Science

Read Explanation

Computer Systems

Read Explanation

Computer Network

Read Explanation

Databases

Read Explanation

Data Representation in Computer Science

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free