What is an index? What is the need to create it on a table ?

Deepak Verma

2 Answers

Like an index in a book, an index in a database lets you quickly find specific information in a table or indexed view.

We can significantly improve the performance of database queries and applications by creating well-designed indexes to support your queries

Syntax: CREATE [UNIQUE] [CLUSTERED | NONCLUSTERED] INDEX index_name ON <table_name | view_name> (column [ASC | DESC] [,...n ])

Example :CREATE UNIQUE CLUSTERED INDEX ENO_IND ON EMP(EMPNO)

CREATE INDEX ENAME_IND ON EMP(ENAME)

vijay kumar singh15y

Hai,

Index is generally created on a table to make search&Retrieval faster.Though we're using Index on small databases,we can't understand the difference in speed.

Index doesn't provide any help to user in front end.It'll make the search process easier and saves time.Try it with a large Database.U can able to get it.

preethi baskaran15y