How does indexing improve query performance?

Answer Posted / praveen

By creating index on single or multiple columns, query
takes index access path instead of full table scan. Full
table scan is costilier operation where it has to visit all
rows in the table whereas index operation just accesses the
index sub table with required hash value and joins with the
basetable using rowid. This improves response time and
performance of the query.

Is This Answer Correct ?    28 Yes 3 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

Explain the term 'row' related to relational database management system?

532


What is meant by a Clique?

589


What are some commonly used bteq scripts?

566


What are the functions of a teradata dba?

600


Describe the between keyword in teradata?

612






Highlight the need for Performance Tuning.

592


Describe primary index in teradata?

587


What is the primary index in teradata?

591


What are the newly developed features of Teradata?

572


What are the updated features of teradata?

582


What is multi insert?

628


During the Display time, how is the sequence generated by Teradata?

617


how do you manage the production space. what are the proactive methods you can take ?

1477


what are the uses of fact table and dimension table in banking project?

4103


What is a three-tier data warehouse?

633