Difference between Cluster and Non-cluster index?
Answers were Sorted based on User's Feedback
Answer / yashpal
Clustered index will be created by default when u
create primary key on a column. only one clustered index is
created per table
Non clustered index will be created automatically when u
create unique key on a column. A table can have no.of
unique keys, so we can create no.of non clustered indexes
per table.
Is This Answer Correct ? | 1 Yes | 0 No |
Answer / ankit murela
cluster index:- (1)only one cluster index can be created.
(2)sort the data physically.
(3)Applied on columns which are not modifier frequencely.
(4)the leaf nodes of a cluster index contain the data pages
non-cluster index:- (1)there can 249 non cluster index per table.
(2)does not sort the data physically.
(3)Applied on columns which are modifier frequencely.
(4)The leaf nodes of a non cluster index does not contain the data pages
Is This Answer Correct ? | 1 Yes | 0 No |
Answer / indranil
The clustered index is SORTED, and the nonclustered index is
UNSORTED.
For example, we have a pile of birth certificates in City
Hall, and we're going to make an index by birthday (birth
date, to be more exact.)
With a nonclustered index, it's like you have a bunch of
paper lists, each paper with a date, and the people born
under that date. You can quickly determine all people who
were born on August 4, 1986. However the papers themselves
are not sorted, so if you wanted to know all people born in
1986, or August 1986, you'll have to go through all the papers.
With a clustered index, the birth certificates themselves
are sorted by birth date, so searching for people born in
1986, or August 1986, January-June 1981, or any date range
is much faster. Also, it is easier to sort all the people by
birth date (since the data is already sorted).
Is This Answer Correct ? | 1 Yes | 0 No |
Answer / prince
clustered index is hemanth index
and
non clustered index is non hemanth index
Is This Answer Correct ? | 1 Yes | 0 No |
Answer / moin khan
Clustered Index
1. Only one per table
2. Faster to read than non clustered as data is
physically stored in index order
Non Clustered Index
1. Can be used many times per table
2.Quicker for insert and update operations than a
clustered index
Is This Answer Correct ? | 1 Yes | 0 No |
Answer / ghanshyam vishwakarma
CLUSTER:- cluster like a pointer that point to one page to
another and get the final data.
NON CLUSTERED INDEX:
Non clustered index will be created automatically when u
create unique key on a column. A table can have no.of
unique keys, so we can create no.of non clustered indexes
per table.
Is This Answer Correct ? | 1 Yes | 0 No |
Answer / sangram nayak
clustered index: if there is any primary key then then its clustered index.only one clustered index can be possible.
Non clusterd index: whenever you are creating any index on any column then that is non clustered index.multile non clusted index is possible.
Is This Answer Correct ? | 1 Yes | 1 No |
Answer / james bond
All are mad with cluster index.
they don't know wht the exact difference.
(All these are book worm.they just a ctrl+C and Ctrl+v and
nothing else)
Clustered index proper way to findd desired data like
rowndex(physical form of data) and non clustered is
mapping of these clustered index in differnt form.
(Don't try to keep as written on your mind. think it and
then use it??)
Is This Answer Correct ? | 62 Yes | 63 No |
Answer / 007
I agree with JAMESBOND's reply....thats the exact thing
happening behind the clustered index and non clustered
index. Remaining answers are all Cut and Paste....
Is This Answer Correct ? | 3 Yes | 7 No |
Answer / rajeev goel
CLUSTER:- cluster like a pointer that point to one page to
another and get the final data.
NON-CLUSTER:- non-cluster like subpart of any part.
for example- content. in side content another subcontent
and so on......
Is This Answer Correct ? | 24 Yes | 109 No |
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