What are indexes? When do you need to create Indexes?
Answers were Sorted based on User's Feedback
Answer / bhagwat sharma
When data volumes increase, organizations are faced with
problems relating to data retrieval and posting. They feel
the need for a mechanism that will increase the speed of
data access. An index, like the index of a book, enables the
database retrieve and present data to the end user with
ease. An index can be defined as a mechanism for providing
fast access to table rows and for enforcing constraints.
| Is This Answer Correct ? | 2 Yes | 0 No |
Answer / rajeev
Index is used for fast searching and batter performance.
| Is This Answer Correct ? | 2 Yes | 1 No |
Answer / murtaza
INDEXES:
1.indexes are used for performance as well as query
optimization issues in database.
2.indexes are by default created when u create an primary or
unique index on a particular column in a table.
3.In sql server there are 2 types of indexes
1.clustered index
2.non clustered index
4.By default non clustered index are created in sql server 2005.
WHEN TO CREATE INDEXES:
1.indexes should be created on the tables which will be used
frequently.
2.it should be created on d tables which has large amount of
data.
| Is This Answer Correct ? | 1 Yes | 0 No |
Answer / radhakrishnan
index : increase the performance of sql statement.
When we create :
1) large number of data in table
2) most of null value in specific column
3) multiple join in sql statement
4) less than 2% of data retrive from table
when we not create :
1) frequently update the table
2) less number of data
Type of Index :
1) clustered index
- primary & unique constaint cretae autoatically for this
index
- only one clustered index per table.
- data sorted physical order
- Eg : book front index
2) non clustered index
- create multiple index per table.
- Eg : book back index
Syntax :
Create index index_name on tablename (column name)
| Is This Answer Correct ? | 1 Yes | 0 No |
How many ways to create table-valued functions?
What is indexed view? How to create it?
What is table level trigger?
Write SQL queries on Self Join and Inner Join.
How to create database with physical files specified in ms sql server?
What are the grouping functions?
what is raid? : Sql server database administration
Explain multiserver query
Issues related in upgrading SQL Server 2000 to 2005 / 2008
Does any body please help me what question's have asked for SSRS in the interview?
How to check if stored procedure is running in sql server?
Explain the collation?
Oracle (3259)
SQL Server (4518)
MS Access (429)
MySQL (1402)
Postgre (483)
Sybase (267)
DB Architecture (141)
DB Administration (291)
DB Development (113)
SQL PLSQL (3330)
MongoDB (502)
IBM Informix (50)
Neo4j (82)
InfluxDB (0)
Apache CouchDB (44)
Firebird (5)
Database Management (1411)
Databases AllOther (288)