MCQs Test!! VB Basic Test !! Essentials of VB !! Creating User Services !! function !! Anatomy !! GK March-2019 !! DATA TYPES IN JAVA !! Classes ,Constructor ,Methods,Inheritance !! Ecology-I !! Biology 2019 !! Gk april 2019 !! Biology (living world) !! Plant anatomy !! CELL STRUCTURES AND FUNCTION !! General biology !! Human physiology !! Data structure !! Ecology-II !! GK TEST !! Reproduction in plants !! Human reproduction !! The ABC of C !! Operating system set1 !! Operating system set2 !! Gk and current affairs !! Animal kingdom !! Number system !! Animal kingdom-II !! Gk TEST-III !! Number series !! Microorganisms !! Interview question in c !! Time and Work !! Percentage !! General history !! Average !! Cells !! Locomotion and Movement !! paging !! Bacteriology !! Page replacement policy !! Secondary memory and Disk scheduling !! Introduction of Nervous System and neurons !! Plant harmones !! Transport and Mineral Nutrition in Plants !! Neurotransmitters !! Modern Indian History !! Photosynthesis in Plants !! Modern Indian History-II !! Plant respiration !! Environment & Biodiversity !! Environment & Biodiversity - II !! Algae, Bryophytes, Pteridophytes !! Area !! Cricket !! Days of the Year (India and the World) !! Plant Pathology - I !! Indian Transport System !! Plant Pathology - II !! Aptitude !! Biology !! Botany !! C language !! Computer Science !! Core Java !! Gate !! GK !! Mysql !! Operating system !! Physics !! VB-Visual Basic !! Zoology

DATABASE & SQL/PLSQL

INDEXES
Previous Home Next

An Indexes is:

  1. SQL server used an internal table structure that provide quick access to rows of a table>
  2. It is totally  based on the values of one or more columns
  3. SQL Server indexes are like the indexes at the back of a book, which help in locating content

Advantage Of Using Indexes

  1. The primary purpose of an index is to provide faster access to data pages
  2. When server searched anything, it searching the index at the place of searching the whole page
  3. Server scan the index and get the address of data storage location and directly access the information
  4. Indexes are also used as a mechanism of enforcing data uniqueness
  5. An index speeds up the processing of queries that use joins or other clauses like ORDER BY or GROUP BY, by allowing to faster access of data
  6. Improve the speed of the execution of queries
  7. Enforce uniqueness of data
  8. Speed up joins between table

 

Disadvantage Of Using Indexes

  1. Indexes does not indexing every column of the table
  2. It takes time to create index>
  3. Each index create requires space to store data along with the original data source-the table
  4. An index gets updated each time the data is modified

Types Of INDEXES

  1. CLUSTERED Index
  2. NONCLUSTERED Index
Previous Home Next