What is clustered and non-clustered indexes?
Answers were Sorted based on User's Feedback
Answer / thangaprabu.n
Apart From above answer,One table Contain only 1 Cluster
index and 249 Non-Cluster Indexes
| Is This Answer Correct ? | 9 Yes | 2 No |
Answer / shubhi
There are clustered and nonclustered indexes. A clustered
index is a special type of index that reorders the way
records in the table are physically stored. Therefore table
can have only one clustered index. The leaf nodes of a
clustered index contain the data pages.
A nonclustered index is a special type of index in which
the logical order of the index does not match the physical
stored order of the rows on disk. The leaf node of a
nonclustered index does not consist of the data pages.
Instead, the leaf nodes contain index rows.
| Is This Answer Correct ? | 9 Yes | 3 No |
Answer / ganesh sial
both index are stored physically but cluster index is create block of key value which more helps to like join,hash condition,more reliable to parent child relation ship
ex:- deptno is primary key for dept table, its create cluster index,
when write query of join like
select a.empno,a.deptno,b.loc from emp a,dept b where a.deptno=b.deptno
this case the cluster index helps to better perfomance
| Is This Answer Correct ? | 1 Yes | 0 No |
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