Cluster Index

Hi All,
I want to know that on a single table how many cluster index we can create.
And can anyone tell me what is actaul benefit of creating Index.
Thanks

What do you mean by "cluster index"? Unlike some databases, like SQL Server, Oracle does not have clustered indexes on heap-organized tables. Oracle does have clusters and index-organized tables depending on the particular problem you're trying to solve.
Justin

Similar Messages

"ORA-1715 : UNIQUE may not be used with a cluster index" but why?

"ORA-1715 : UNIQUE may not be used with a cluster index" but why and what "may" means here? Any comments will be welcomed, thank you and best regards;
show rel
release 1002000300
CREATE CLUSTER sc_srvr_id (
srvr_id NUMBER(10)) SIZE 1024;
SELECT cluster_name, tablespace_name, hashkeys,
degree, single_table FROM user_clusters;
CREATE UNIQUE INDEX idx_sc_srvr_id ON CLUSTER sc_srvr_id;
ERROR at line 1:
ORA-01715: UNIQUE may not be used with a cluster index
CREATE INDEX idx_sc_srvr_id ON CLUSTER sc_srvr_id;
SELECT index_name, index_type, tablespace_name
FROM user_indexes where index_name like '%SRVR%' ;
CREATE TABLE cservers (
srvr_id    NUMBER(10),
network_id NUMBER(10),
status     VARCHAR2(1),
latitude   FLOAT(20),
longitude FLOAT(20),
netaddress VARCHAR2(15))
CLUSTER sc_srvr_id (srvr_id);
ALTER TABLE cservers add constraint pk_srvr_id primary key (srvr_id ) ;
SELECT index_name, index_type, tablespace_name
FROM user_indexes where index_name like '%SRVR%' ;
INDEX_NAME                     INDEX_TYPE
TABLESPACE_NAME
IDX_SC_SRVR_ID                 CLUSTER
USERS
PK_SRVR_ID                     NORMAL
USERSdo we really need another pkey index here?

"May" has different meanings, one of which is:
(used to express opportunity or permission)
Metalink note 19067.1 says:
This is not permitted.
... which agrees with the above meaning of it.
Besides these, it does not make any sense to me to create a unique index on a cluster. You can have primary keys in the tables you include in the cluster, it depends on your business requirement. But why do you need a unique index on a cluster?

Cluster indexe

Hi,
what is a cluster indexe in ORACLE database?
Of cours I looked for it :
http://www.oracle.com/pls/db102/search?word=%27cluster+indexes%27&partno=But no definition other than :
A cluster provides an optional method of storing table data. A cluster is made up of a group of tables that share the same data blocks.
It seems that it is not the same as in MS SQLSERVER :
Clustered indexes sort and store the data rows in the table based on their key values.Thanks in advance.

user522961 wrote:
Hi,
what is a cluster indexe in ORACLE database?
It seems that it is not the same as in MS SQLSERVER :
The closest match that Oracle has for the clustered index is the index-organized table - check the SQL Reference manual for "Create table" and "organization index" - but in Oracle the index has to be the primary key (i.e. unique and non-null).
Regards
Jonathan Lewis
http://jonathanlewis.wordpress.com
http://www.jlcomp.demon.co.uk
To post code, statspack/AWR report, execution plans or trace files, start and end the section with the tag {noformat}{noformat} (lowercase, curly brackets, no spaces) so that the text appears in fixed format.
There is a +"Preview"+ tab at the top of the text entry panel. Use this to check what your message will look like before you post the message. If it looks a complete mess you're unlikely to get a response. (Click on the +"Plain text"+ tab if you want to edit the text to tidy it up.)
+"I believe in evidence. I believe in observation, measurement, and reasoning, confirmed by independent observers. I'll believe anything, no matter how wild and ridiculous, if there is evidence for it. The wilder and more ridiculous something is, however, the firmer and more solid the evidence will have to be."+
Isaac Asimov

What does synchronizing the cluster index do?

what does synchronizing the cluster index do? Does it index newly added/ updated documents to the clusters? please explain.

In Folio Builder Panel? See http://helpx.adobe.com/digital-publishing-suite/help/create-articles.html#change_article_p roperties
Neil

View cluster index affecting performance

Hi All,
We have a simple delete and insert script for a table, but the table has a dependency to 2 view cluster index, So whenever am going to insert and update the parent table it is going to update the view cluster index, But while updating the view cluster index
it runs the view cluster index again (like executing the view) hence it affect the performance.
Please advise Is there any way to skip the view execution? because this view is already a heavy operation with many logial reads..
Also advise view cluster index in simple terms because when i google I can not get a concrete answers. Since it's a index can we rebuild or reorg? forgive if my question is stupid... :)
Best Regards Moug

Hi,
There's a good review here on designing indexed views, just for your curiosity - https://technet.microsoft.com/en-us/library/ms187864%28v=sql.105%29.aspx?f=255&MSPPError=-2147217396
There is no way to skip updating the view if it is a clustered view. It has to maintain the integrity of the data, so if it's an indexed view, when the table is updated in any way, it will also have to update the view. As you are seeing, there is a penalty
to this.
If you are doing a lot of inserts/deletes at once, it is sometimes a good idea to drop the index from the view, do your batch of inserts/updates, and then reapply the index. This way you don't have to process each update on the fly, it will just do it once
when you rebuild the index.
Also, yes, you can treat it as a standard index and rebuild/reorg it with all of your other indexes.
Thanks,
Stephen
Please click "Mark as Answer" if you found my post helpful. Thanks, Stephen.

Array of cluster label

I have an array of clusters that are PID parameters for the NI motion card (one for each axis).
I would like to change the label for the array based on the cluster (index) that is being displayed.
When I try to do this, I get the error
Error 1073 occurred at Property Node (arg 1) in TuneNew.vi
Possible reason(s):
LabVIEW: This property is writable only when the VI is in edit mode, or this method is available only when the VI is in edit mode.
How do I change the label?
Is it possible, or do I need to use a workaround of putting up a text string and changing that?
Thanks in advance

Hi jspaarg,
You only need to tweek your code a bit to make this work!
Instead of displaying the Array label, you want to hide the label, but display the "Caption". The caption can be changed.
cheers
When they give imbeciles handicap-parking, I won't have so far to walk!

Heap tables and index organized tables

I performing migration from mssql server to oracle 10gr2 rdbms, in mssql all tables have clustered pk, index. Is it necessary to use index organized tables for that migration, or enough ordinal heap organized tables and what differences between those tables, and mssql tables
Thanx

In Oracle, the typical table is a standard 'heap' table. Stuff goes into the heap table randomly, and randomly comes out.
An Index Organizaed Tables is somewhat similar to a Cluster Index in SS. It can have some performance advantages over heap tables - when the heap table has an associated index on the primary key.
The IOT can also have some disadvantages, such as the need for an Overflow table to handle the extra data when a row doesn't conveniently fit in a block (implying multiple I/Os), and an extra translation table if bitmap indexes are required (implying extra I/Os).
An unintelligent developer will generally believe that Oracle and SQL Server are the same - after all they both run SQL - and will attempt to port by a simple translation of syntax.
An intelligent developer will test both styles of tables, during a port. Such a developer will also be quick to learn about the changes in internals (such as locking mechanisms) and will realize that different styles of coding are required for many application situations.
I recommend reading Tom Kyte's books to get handle on pros and cons as well as testing techniques to help a developer become intelligent.

Cluster and Personalization server

Hi:
How do I set my Personalization/Portal server up to work in WL cluster ?
Thank You
David L. Wasler
[email protected]

It's just like setting up Weblogic Server (WLS) in a cluster. The Weblogic
Personalization Server (WLPS) is a framework built on top of WLS. Check the
administration documents at
http://www.weblogic.com/docs51/cluster/index.html
Ture Hoefner
BEA Systems, Inc.
1655 Walnut Street; suite 200
Boulder, CO 80302
www.beasys.com

SQL Server 2014 Bug - with Clustered Index On Temp Table with Identity Column

Hi,
Here's a stored procedure. (It could be shorter, but this will show the problem.)
CREATE PROCEDURE dbo.SGTEST_TBD_20141030 AS
IF OBJECT_ID('TempDB..#Temp') IS NOT NULL
DROP TABLE #Temp
CREATE TABLE #Temp
Col1 INT NULL
,Col2 INT IDENTITY NOT NULL
,Col3 INT NOT NULL
CREATE CLUSTERED INDEX ix_cl ON #Temp(Col2)
SET IDENTITY_INSERT #Temp ON;
RAISERROR('Preparing to INSERT INTO #Temp...',0,1) WITH NOWAIT;
INSERT INTO #Temp (Col1, Col2, Col3)
SELECT 1,2,3
RAISERROR('Insert Success!!!',0,1) WITH NOWAIT;
SET IDENTITY_INSERT #Temp OFF;
In SQL Server 2014, If I execute this (EXEC dbo.SGTEST_TBD_20141030) It works. If I execute it a second time - It fails hard with:
Msg 0, Level 11, State 0, Line 0
A severe error occurred on the current command. The results, if any, should be discarded.
Msg 0, Level 20, State 0, Line 0
A severe error occurred on the current command. The results, if any, should be discarded.
In SQL Server 2012, I can execute it over and over, with no problem. I've discovered two work-a-rounds:
1) Add "WITH RECOMPILE" to the SP CREATE/ALTER statement, or
2) Declare the cluster index in the TABLE CREATE statement, e.g. ",UNIQUE CLUSTERED (COL2)"
This second option only works though, if the column is unique. I've opted for the "WITH RECOMPILE" for now. But, thought I should share.

Hi,
I did not get any error Message:
CREATE TABLE #Temp
Col1 INT NULL
,Col2 INT IDENTITY NOT NULL
,Col3 INT NOT NULL
CREATE CLUSTERED INDEX ix_cl ON #Temp(Col2)
SET IDENTITY_INSERT #Temp ON;
RAISERROR('Preparing to INSERT INTO #Temp...',0,1) WITH NOWAIT;
INSERT INTO #Temp (Col1, Col2, Col3)
SELECT 1,2,3
RAISERROR('Insert Success!!!',0,1) WITH NOWAIT;
SET IDENTITY_INSERT #Temp OFF;
SELECT * FROM #Temp
OUTPUT:
Col1 Col2
Col3
1 2 3
1 2 3
1 2 3
Select @@version
--Microsoft SQL Server 2012 (SP1) - 11.0.3000.0 (X64)
Oct 19 2012 13:38:57
Copyright (c) Microsoft Corporation
Enterprise Edition (64-bit) on Windows NT 6.1 <X64> (Build 7601: Service Pack 1)
Thanks Shiven:) If Answer is Helpful, Please Vote

Hash Cluster Tables vs Partitioning

Hi All,
Can we create partition on Cluster tables?
As per understanding Cluster can give excellent performance if used carefully, in our case we need to purge our data also.
We can purge the partitions easly.
Can you help me for the comparion of these two objects?
Thanks
Sandeep

No , Oracle does not support this.
http://download.oracle.com/docs/cd/B28359_01/server.111/b32024.pdf (page 4-19).
The rules for partitioning indexes are similar to those for tables:
■ An index can be partitioned unless:
– The index is a cluster index.
– The index is defined on a clustered table
Thanks
http://swervedba.wordpress.com/

Compression on table and on clustered index

Hi all,
if I had a table with a clustered index on it, is it the same to rebuild the table with compression and rebuild the clustered index with compression?
Is this
ALTER TABLE dbo.TABLE_001 REBUILD PARTITION = ALL WITH (DATA_COMPRESSION = ROW, ONLINE=ON)
Equivalent to this?
ALTER INDEX PK_TABLE_001 ON dbo.TABLE_001 REBUILD WITH (DATA_COMPRESSION=ROW, ONLINE=ON)
where PK_TABLE_001 is the clustered index of the table TABLE_001

Andrea,
Cluster index is table itself organized according to clustering key value. So if you apply compression on CI means internally table would be compressed and because cluster index includes all columsn of the table so complete table would be compressed.
Please mark this reply as answer if it solved your issue or vote as helpful if it helped so that other forum members can benefit from it
My Technet Wiki Article
MVP

Types of Oracle indexes

Can some one explain what all are the types of indexes in Oracle

Hi,
In short there are only 2 types
1)B-tree indexes
2)Bitmap indexes
These 2 types are subdivided as follows:
*1)B-tree indexes*
These indexes are the standard index type. They are excellent for primary key and highly-selective indexes. Used as concatenated indexes, B-tree indexes can retrieve data sorted by the indexed columns. B-tree indexes have the following subtypes:
*Index-organized tables
An index-organized table differs from a heap-organized because the data is itself the index.
*Reverse key indexes
In this type of index, the bytes of the index key are reversed, for example, 103 is stored as 301. The reversal of bytes spreads out inserts into the index over many blocks.
*Descending indexes
This type of index stores data on a particular column or columns in descending order.
*B-tree cluster indexes
This type of index is used to index a table cluster key. Instead of pointing to a row, the key points to the block that contains rows related to the cluster key.
*2)Bitmap indexes:*
•Bitmap and bitmap join indexes
In a bitmap index, an index entry uses a bitmap to point to multiple rows. In contrast, a B-tree index entry points to a single row. A bitmap join index is a bitmap index for the join of two or more tables.
*Function-based indexes
This type of index includes columns that are either transformed by a function, such as the UPPER function, or included in an expression. B-tree or bitmap indexes can be function-based.
*Application domain indexes
This type of index is created by a user for data in an application-specific domain. The physical index need not use a traditional index structure and can be stored either in the Oracle database as tables or externally as a file.
Best regards,
Rafi.
http://rafioracledba.blogspot.com/

How to create a cluster on existing table

how to create a cluster on existing table

user8949393 wrote:
how to create a cluster on existing tableAFAIK you can't. You have to create the cluster from scratch, something like
--cluster key can be just one column also
CREATE CLUSTER s_emp_dept_ic (deptno NUMBER(7), dname varchar2(30));
CREATE TABLE emp(
DEPTNO NUMBER(7),
DNAME VARCHAR2(30),
EMPNO NUMBER(4),
ENAME VARCHAR2(30)
--cluster clause puts table in cluster. Deptno, dname are table columns in
--cluster key
CLUSTER s_emp_dept_ic (deptno,dname);
--a cluster index must be created before any data is inserted
--the index columns used come from the cluster key from CREATE CLUSTER
CREATE INDEX s_emp_idx ON CLUSTER s_emp_dept_ic;

Clustered indexes

Hi,
Could anyone throw some light on how exactly the clustered indexes function in Oracle?
Is it that as soon as we create an index, it is a clustered index by default..?
e,.g create index idx1 on EMP (empno);
so idx1 is a clustered index here.
Many Thanks.
Haribol
Krsna

Hi,
A cluster is a schema object that contains data from one or more tables, all of which have one or more columns in common. Oracle Database stores together all the rows from all the tables that share the same cluster key.
You can create a cluster index on a cluster.
CREATE INDEX idx1 ON CLUSTER scott_clst;
Check this link for more information.
http://download-uk.oracle.com/docs/cd/B14117_01/server.101/b10759/statements_5001.htm
Thanks

Cluster Info

Hi,
i am getting below INFO and errors in logs i want to what each of them is occuring, can any one help me in my understanding.
####<Sep 26, 2012 10:49:55 AM CDT> <Info> <Cluster> <Server3> <server3a> <[ACTIVE] ExecuteThread: '43' for queu
e: 'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <> <1348674595168> <BEA-000112> <Removing decs5a jvmid:16589531
05634154558S:10.110.7.115:[8011,8011,-1,-1,-1,-1,-1]:decs:decs5a from cluster view due to timeout.>
####<Sep 26, 2012 10:49:59 AM CDT> <Info> <Cluster> <<Server3> <server3a> <weblogic.cluster.MessageReceiver> <<W
LS Kernel>> <> <> <1348674599925> <BEA-000115> <Lost 2 multicast message(s).>
####<Sep 26, 2012 10:50:00 AM CDT> <Info> <Cluster><Server3> <server3a> <[ACTIVE] ExecuteThread: '16' for queu
e: 'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <> <1348674600471> <BEA-000111> <Adding decs5a with ID 16589531
05634154558S:10.110.7.115:[8011,8011,-1,-1,-1,-1,-1]:server:server5a to cluster: decscluster view.>
####<Sep 26, 2012 10:50:05 AM CDT> <Info> <Cluster> <Server3> <server3a> <[ACTIVE] ExecuteThread: '36' for queu
e: 'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <> <1348674605176> <BEA-000128> <Updating 1658953105634154558S:
10.110.7.115:[8011,8011,-1,-1,-1,-1,-1]:server:server5a in the cluster.>
####<Sep 26, 2012 10:50:24 AM CDT> <Info> <Cluster> <Server3> <server3a> <weblogic.cluster.MessageReceiver> <<W
LS Kernel>> <> <> <1348674624426> <BEA-000115> <Lost 1 multicast message(s).>
javax.ejb.EJBException
####<Sep 26, 2012 11:26:16 AM CDT> <Warning> <JNDI> <dal604se115.dynamex.com> <decs5a> <[ACTIVE] ExecuteThread: '12' for queu
e: 'weblogic.kernel.Default (self-tuning)'> <kwplatt> <> <> <1348676776719> <BEA-050007> <An attempt was made to look up non-
versioned global resource "" from an application version "administration.war [Version=3.20.1.1398]". This can potentially cau
se conflict of the global resource usages among multiple application versions.>
####<Oct 3, 2012 2:27:13 PM CDT> <Error> <Cluster> <server1> <server1a> <[ACTIVE] ExecuteThread: '7' for queue:
'weblogic.kernel.Default (self-tuning)'> <<anonymous>> <> <> <1349292433387> <BEA-000117> <Received a stale replication reques
t for object 8042261441738434683.>
####<Oct 3, 2012 10:51:08 PM CDT> <Warning> <Cluster> <server1> <server1a> <[ACTIVE] ExecuteThread: '6' for queu
e: 'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <> <1349322668940> <BEA-000184> <This server did not attempt to
renew its lease for 698 seconds. The server may restarted or migrated.>
####<Oct 3, 2012 10:51:08 PM CDT> <Info> <Cluster> <<server1> <server1a> <[ACTIVE] ExecuteThread: '6' for queue:
'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <> <1349322668949> <BEA-000185> <Despite the delay in the lease-ren
ewing thread, the server has successfully renewed its lease. It is no longer in imminent risk of being migrated or restarted.>
####<Oct 3, 2012 10:40:23 PM CDT> <Info> <Server> <server3> <server3a> <[ACTIVE] ExecuteThread: '17' for queue:
'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <> <1349322023616> <BEA-002634> <The server "AdminServer" disconnec
ted from this server.>
####<Oct 3, 2012 10:40:20 PM CDT> <Info> <Server> <server5> <server5a> <[STANDBY] ExecuteThread: '21' for queue:**
'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <> <1349322020161> <BEA-002634> <The server "AdminServer" disconne**
cted from this server.>**
Thanks in advance..!
Imran khan.

Most of these are around clustering. I would suggest you read the section on clustering in the documentation, it will explain most of this
http://docs.oracle.com/cd/E11035_01/wls100/cluster/index.html
For instance
####<Sep 26, 2012 10:49:59 AM CDT> <Info> <Cluster> <<Server3> <server3a> <weblogic.cluster.MessageReceiver> <<W
LS Kernel>> <1348674599925> <BEA-000115> <Lost 2 multicast message(s).>
####<Sep 26, 2012 10:50:00 AM CDT> <Info> <Cluster><Server3> <server3a> <[ACTIVE] ExecuteThread: '16' for queu
e: 'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <1348674600471> <BEA-000111> <Adding decs5a with ID 16589531
05634154558S:10.110.7.115:[8011,8011,-1,-1,-1,-1,-1]:server:server5a to cluster: decscluster view.>
is to do with communication between the servers in a cluster, using multicast, and how the server is losing (not receiving or not receiving a response for) multicast messages broadcast to the cluster.
####<Oct 3, 2012 2:27:13 PM CDT> <Error> <Cluster> <server1> <server1a> <[ACTIVE] ExecuteThread: '7' for queue:
'weblogic.kernel.Default (self-tuning)'> <<anonymous>> <1349292433387> <BEA-000117> <Received a stale replication reques
t for object 8042261441738434683.>
This is to do with session replication between the servers.
####<Oct 3, 2012 10:51:08 PM CDT> <Warning> <Cluster> <server1> <server1a> <[ACTIVE] ExecuteThread: '6' for queu
e: 'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <1349322668940> <BEA-000184> <This server did not attempt to
renew its lease for 698 seconds. The server may restarted or migrated.>
This is leasing and how the server is not contacting the master manager server to maintain it's lease.
####<Oct 3, 2012 10:51:08 PM CDT> <Info> <Cluster> <<server1> <server1a> <[ACTIVE] ExecuteThread: '6' for queue:
'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <1349322668949> <BEA-000185> <Despite the delay in the lease-ren
ewing thread, the server has successfully renewed its lease. It is no longer in imminent risk of being migrated or restarted.>
as is this, only here the lease is taken.
####<Oct 3, 2012 10:40:20 PM CDT> <Info> <Server> <server5> <server5a> <[STANDBY] ExecuteThread: '21' for queue:**
'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <1349322020161> <BEA-002634> <The server "AdminServer" disconne**
cted from this server.>**
this means that the managed server can no reach the admin server, probably as it's been restarted.

Cluster Index

Similar Messages

Maybe you are looking for