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Unit 11: Query Processing and Optimization
Sartaj Singh, Lovely Professional University

unit 11: Query processing and optimization notes

contents
Objectives
Introduction
11.1 Query Processing: An Overview
11.2 Description and Requirements for Data Warehouse Queries
11.2.1 Understanding Bitmap Filtering
11.2.2 Optimized Bitmap Filtering Requirements
11.3 Writing your own Queries

11.4 Query Processing Techniques
11.4.1 Relational Model
11.4.2 Cost Model
11.4.3 Full Scan Technique
11.4.4 Scanning with Index Techniques
11.4.5 RID Index Technique
11.4.6 BitMap Index Technique
11.4.7 Inverted Partitioned Index Technique
11.5 Comparison of the Query Processing Strategies
11.6 Summary
11.7 Keywords
11.8 Self Assessment
11.9 Review Questions

11.10 Further Readings

objectives

After studying this unit, you will be able to:
l z Explain query processing

l z Know description and requirements for data warehouse queries
l z Describe query processing techniques
introduction

The Query Language SQL is one of the main reasons of success of RDBMS. A user just needs
to specify the query in SQL that is close to the English language and does not need to say how
such query is to be evaluated. However, a query needs to be evaluated efficiently by the DBMS.
But how is a query-evaluated efficiently? This unit attempts to answer this question. The unit

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