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SQL primary key add INCLUDE column

Posted on 2009-07-15
Last Modified: 2012-05-07
I have a table with a GUID primary key, is it possible to add INCLUDE fields to this cluster index, if so could you give me the syntax to alter this index as I do not want to delete it this would effect existing relationships with other tables etc. I know it is possible to add include fields to other indexes.
Question by:freshnet
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Expert Comment

by:Raja Jegan R
ID: 24858806
Hope this helps:
CREATE TABLE test ( a uniqueidentifier PRIMARY key, b int, c int);
CREATE nonCLUSTERED INDEX ix_test ON test ( a) INCLUDE (b,c)

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Expert Comment

ID: 24858846
BTW...if your primary key is clustered, you will not need to include a column. By default, all columns in a clustered index are "included"...so this would only apply to an NC primary key
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Expert Comment

ID: 24858857
rrjegan, your example really isn't applicable....by default the primary key is clustered unless you specify otherwise.
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Accepted Solution

Raja Jegan R earned 500 total points
ID: 24858945
>> rrjegan, your example really isn't applicable

I misread the question. Thanks for pointing it out.


>> is it possible to add INCLUDE fields to this cluster index
   No.. You cant create clustered index with INCLUDE clause.

Hope this clarifies.
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Expert Comment

ID: 24858955
No worries.  Just wanted to clear it up.  :)

Author Closing Comment

ID: 31603708
but why is this do you think?
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Expert Comment

ID: 24859653
pretty sure a split would have been necessary here....
LVL 57

Expert Comment

by:Raja Jegan R
ID: 24859752
For your reference,

INCLUDE ( column [ ,... n ] )
    Specifies the non-key columns to be added to the leaf level of the nonclustered index. The nonclustered index can be unique or non-unique.
    Column names cannot be repeated in the INCLUDE list and cannot be used simultaneously as both key and non-key columns. Nonclustered indexes always contain the clustered index columns if a clustered index is defined on the table. For more information, see Index with Included Columns.


>> pretty sure a split would have been necessary here....

No concerns from my side as you directed me correctly.

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