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 |
how to create a database in oracle?
Does google use sql?
What is cartesian join in sql?
take one table is t1 and in that column name is f1 f1 column values are 200 5000 3000 7000 300 600 100 400 800 400 i want display the values asc and desc in a single output. sample output is f1.a 100 200 300 400 500 600 etc...... and f1.d is 5000 4000 3000 2000 1000 etc...
what are the different tables present in mysql, which type of table is generated when we are creating a table in the following syntax: create table employee (eno int(2),ename varchar(10)) ? : Sql dba
What is a common use of group by in sql?
Why is sharding used?
What is a trigger in sql?
What is the function that is used to transfer a pl/sql table log to a database table?
write sub query for eliminating duplicate rows using analytical function?
Do we need commit after truncate?
Can pl sql procedure have a return statement?