Duty Free!!

SQL Write-Ahead Overhead…

SQL Server: Rebuild Indexes based on Fragmentation.

In the recent past there were quiet a few friends of mine asking

for a script to rebuild indexes selectively-based on Defragmentation.

http://sql-server-performance.com/Community/forums/t/20515.aspx 

is a nice discussion for this kinda script. The script listed by ‘thomas’

is  a good/simple one.One thing this script doesnt do, is rebuilding

indexes on a View in SQL 2005. This can be attained by a small change

– try changing the

“so.type =’U'” to “so.type in (‘U’,’V’)”.

Also, this script does an offline operation, Reindexing. Inorder to have

this  changed to Defragment, which is an online operation, change the code

SELECT @execstr = ‘DBCC DBREINDEX (‘ + RTRIM(@tablename) + ‘,
‘ + RTRIM(@indexname) + ‘) WITH NO_INFOMSGS’

to

SELECT @execstr = ‘DBCC INDEXDEFRAG ( 0’ + RTRIM(@tablename) + ‘,
‘ + RTRIM(@indexname) + ‘) WITH NO_INFOMSGS’
SELECT (@execstr)
EXEC (@execstr)

SELECT @execstr = ‘UPDATE STATISTICS ON ‘ + RTRIM(@tablename) + ‘.
‘ + RTRIM(@indexname) + ‘ WITH FULLSCAN’

Remember that Reindexing will update the statistics while the

Indexdefrag doesnt. Hence it was explicitly provided with an update

statistics step in the above snippet.  Hope this helps!!

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September 25, 2008 - Posted by | SQL Server

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