Primary Key With Non-clustered Index

Dec 11, 2007

Dear all,


I want to keep certain archive data in certain tables. One such table is currently about 190 GB in size. It has a primary key with clustered index and three non-clustered indexes. The type of queries fired are strictly selects (daily) and inserts (only monthly).

Question: Is it advisable to have a non-clustered index on the primary key column?.....I am finding that the insert performance is getting hurt due to presence of clustered index on such a large table (190 GB).

Let me know your views.


Regards,

Chetan

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We are going to use SQL Sever change tracking. The problem is that some of our tables, which are to be tracked, have no primary keys. There are only unique clustered indexes. The question is what is the best way to turn on change tracking for these tables in our circumstances.

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[EventTypeEnum] [tinyint] NOT NULL,

[code]....

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Jul 19, 2013

I have created two tables. table one has the following fields,

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         table two has the following fields,
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Dear All,
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Vinod
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Jul 18, 2007

Hi,



I have created a very simple table. Here is the script:

if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[IndexTable]') and OBJECTPROPERTY(id, N'IsUserTable') = 1)
drop table [dbo].[IndexTable]

GO

CREATE TABLE [dbo].[IndexTable] (
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[Code] [nvarchar] (50) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL
) ON [PRIMARY]

GO


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GO

ALTER TABLE [dbo].[IndexTable] ADD
CONSTRAINT [PrimaryKeyOnId] PRIMARY KEY NONCLUSTERED
(
[Id]
) ON [PRIMARY]
GO



The records that i added are:

Id Code

1 a
2 b
3 aa
4 bb

Now when i query like

Select * from IndexTable

I expect the results as:

Id Code

1 a
3 aa
2 b
4 bb

as i have the clustered index on column Code.

But i m getting the results as:

Id Code

1 a
2 b
3 aa
4 bb

as per the primary key order that is a non clustered index.

Can anyone explain why it is happening?


Thanks

Nitin

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Hi all,


I have a huge table with million of rows, which has ONE Clustered index associated with the PRIMARY KEY, and there are some NON_Clustered indexes.


So,now i decided that, i dont need any more indexes ( not even one) on that table, but i need to maintain primary key on that table.


(a) So, how can i accomplish this (i.e.) having primay key but not having indexes on the table.


Thanks.

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the query:

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FROM Asset a WHERE a.AssociationGuid IN (
SELECT ada.DataAssociationGuid FROM AssociationDataAssociation ada
WHERE ada.AssociationGuid = '568B40AD-5133-4237-9F3C-F8EA9D472662')

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expanding the inner select into a list of guids the query runs instantly:

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'0F9C1654-9FAC-45FC-9997-5EBDAD21A4B4',
'52C616C0-C4C5-45F4-B691-7FA83462CA34',
'C95A6669-D6D1-460A-BC2F-C0F6756A234D')

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The tables involved:

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I'd include .sqlplan files or screenshots, but I don't see a way to attach them. 

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FROM Asset a WITH (INDEX (IX_Asset_AssociationGuid)) WHERE
a.AssociationGuid IN (
SELECT ada.DataAssociationGuid FROM AssociationDataAssociation ada
WHERE ada.AssociationGuid = '568B40AD-5133-4237-9F3C-F8EA9D472662')

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Hi everybody!

I just ran the Database Engine Tuning Advisor on a relative complex query to find out if a new index might help, and in fact it found a combination that should give a performance gain of 94%. Fair enough to try that.

What I wonder about: The index I should create contains 4 columns, the last of them being the Primary Key column of the table, which is also my clustered index for the table. It is an identity integer btw.

I think I remember that ANY index does include the clustered one as lookup into the data, so having it listed to the list of columns will not help. It might at worst add another duplicate 4 bytes to each index entry.

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Thanks for suggestions!
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Dec 5, 2007



Dear All.

We had Teradata 4700 SMP. We have moved data from TD to MS_SQL SERVER 2003. records are 19.65 Millions.

table is >> Order_Dtl

Columns are:-

Client_ID varchar 10
Order_ID varchar 50
Order_Sub_ID decimal
.....
...
..
.
Pk is (ClientID+OrderId+OrderSubID)

Web Base application or PDA devices use to initiate the order from all over the country. The issue is this table is not Partioned but good HP with 30 GB RAM is installed. this is main table that receive 18,0000 hits or more. All brokers and users are using this table to see the status of their order.

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Query takes to much time when ever server receive more querys. some orther indexes are also created on the same table like (OrderDate, OrdCreate Date and Status)

My Question are:-


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Q3. I want to check what indexes has been used? on what search?

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My Limitation is i Dont Create a Partioned table. I dont have permission to do it.



In Teradata we had more than 4 tb record of CRM data with no issue. i am not new baby in db line but not expert in sql server 2003.


I am thank u to all who read or reply.

Arshad

Manager Database
Esoulconsultancy.com

(Teradata Master)
10g OCP










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Hi everyone,
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