Fragmentation
Mar 29, 2001What DBCC or otherwise one would be able to find table fragmentation in SQL 7 and how to take some proactive actions ?
Thanks very much for your time.
-Tim
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Fragmentation
May 13, 2008i want to do fragmentation using SQL 2005 Express. Can their be any helping material for making fragmentation. Any Example
View 2 Replies View RelatedFragmentation
Jun 1, 2004Would someone please let me know which is the better way to reduce fragmentation on Windows:NT drive?
dbcc indexdefrag
or
dbcc reindex
or
dropping and recreating indexes through SQL?
Thanks
Vinnie
Fragmentation?
Jul 27, 2007Sql Server 2000.
For simplicity, I am avoiding minor details.
Here is a scenario.
Create Table T (T_ID int PK, €¦..) and this table is referenced by 20 other places on T_ID.
And these 20 tables have T_ID as PK or part of PK.
We have large volume of deletes in T and in the other 20 tables based on T_ID.
Once the deletes are done, will dropping and re-creating the FK€™s that reference the T_ID
help reduce the fragmentation caused by the deletes?
Table Fragmentation
May 8, 2001hi all,
i have inherited a database running on sql7 sp2. a lot of the tables do not have a clustered index. some of these tables are highly fragmented. below is a sample of the dbcc showcontig output
TABLE level scan performed.
- Pages Scanned................................: 104934
- Extents Scanned..............................: 13124
- Extent Switches..............................: 13123
- Avg. Pages per Extent........................: 8.0
- Scan Density [Best Count:Actual Count].......: 99.95% [13117:13124]
- Extent Scan Fragmentation ...................: 5.84%
- Avg. Bytes Free per Page.....................: 7757.4
- Avg. Page Density (full).....................: 4.16%
this table has 5 non-null char columns whose total length is 43 chars and the table occupies about 900 mb for only about 670,000 rows!
select on the table sucks!
since there is no clustered index i have to rebuild the table to remove the fragmentation. is there a way to reorganize the table without recreating it?
thanx
:-)
hemant
Fragmentation -Urgent
Oct 13, 2000Hi!
I have a problem with defragmenting the tables. When i ran dbcc showcontig for the tables, it shows 94%, 50%, 33% fragmentations . I have rebuild indexes on all those tables and ran dbcc showcontig again but still it shows the same % of fragmentations. Is there any way to remove fragmentation on all the tables completely. Any help would be appreciated.
Thanks,
Saran
Disk Fragmentation && SQL
Apr 14, 2004One of my production servers has been determined to be 92% fragmented.
What's the proper procedure for defraging a database server?
I couldn't find anything very helpful in BOL, nor Knowledge Base.
Sidney Ives
Database Administrator
Sentara Healthcare
Disk Fragmentation
Aug 9, 2004What's the best way to find out if disk fragmentation on Windows 2000 Server is affecting SQL Server performance?
If disk fragmentation is shown to be a cause of performance problems, what are the recommendations for a disk fragmentation strategy? eg. use the win 2000 built in disk defrag utility or buy a 3rd party product like DiskKeeper? How much of an overhead is a product like DiskKeeper that defrags in the background?
Clive
Database Fragmentation
Oct 1, 2004Hello,
How can I mesure the database fragmentation ? Cause DBCC SHOWCONTIG shows obects fragmentation only. I would like to see the whole database fragmentation.
Thanks for help
Index Fragmentation
Jun 22, 2008What functions of tools do you use for managing index fragmentation?
DBCC?
I am working through MS Press SQL 2005 book and it mentions the
sys.dm_db_index_physical_stats function? It then give an example of code which is very involved.
Does anybody use this function?
Thanks
Index Fragmentation
May 10, 2007before rebuild index
---------------------
tablenameIndexname
avg_fragmentation_in_percent
Payoff_QuotePK_Payoff_QuoteDetail
83.3333333333333
ALTER INDEX ALL ON Payoff_Quote REBUILD
after issue the above statement result remain same.
Index Fragmentation
Jun 24, 2007Hi
When I run sys.dm_db_index_physical_stats on AdventureWorks.Production.Product, I get an average fragmentaion of 46%, 0%, 25% & 50% on the Indexes.
I run ALTER INDEX ALL ON AdventureWorks.Production.Product
REBUILD WITH (FILLFACTOR = 80, SORT_IN_TEMPDB = ON,
STATISTICS_NORECOMPUTE = ON)
and the index fragmentation does not change...
Why is that?? I have tried refreshing the table and the statistics but why does it look like rebuilding the indexes has done nothing?
Index Fragmentation In The DMV
Sep 25, 2007I have a nice script that will look at the index fragmentation by using the DMV (sys.dm_db_index_physical_stats) and if its above a specificed threshhold, it will rebuild or reorg the index.
What I have noticed is that even after reorging and/or rebuilding the index, the fragmentation percent in the DMV does not change for some indexes. Other indexes are updated just fine.
Is this a result of updating statistics? Why would the fragmentation change for some indexes and not others? Why does it seem no matter how much rebuilding or reorging is done, the fragmentation percent for some indexes does not change?
- Eric
Heavy Fragmentation
May 8, 2007I'm attempting to debug some query timeouts on a production server.
Several tables involved in this query have logical scan fragmentation levels around 10%, and extent scan fragmentation levels 90%+.
Running INDEXDEFRAG or DBREINDEX reduces the logical scan fragmentation down to almost 0%, but the extent scan fragmentation stays upwards of 90%.
Why? What can I do to get this fragmentation down? Is it because this particular index is on a GUID?
SQL Backup (bak) Fragmentation
Dec 13, 2006We backup a lot of SQL databases. The db admin uses SQL to dump the databases to a *.bak file on a network share, then we pick them up to tape.
The problem is that for some reason, the backup files are MASSIVELY fragmented, which kills our backup speed to tape (via Netbackup Enterprise). If I defragment the drive (via the built-in tool on Win2K3 or PerfectDisk 8) our speed to tape more than doubles (can go from 16MB/sec to 36MB/sec). However, after the next SQL backup, the drive is completley fragmented once again (around 70%).
Is there any way to improve how these files are written to disk (to keep them relatively in one piece)? For some reason it appears this is a bigger issue with the SQL backup files than any other file type. Thanks.
Jim B
Fragmentation Does Not Change
Aug 8, 2007I am running this script to see the fragmentation of indexes.
SELECT a.database_id
,a.object_id
,a.index_id
,b.name
,a.avg_fragmentation_in_percent
FROM sys.dm_db_index_physical_stats (7,NULL, NULL, NULL, NULL) AS a
JOIN sys.indexes AS b
ON a.object_id = b.object_id
AND a.index_id = b.index_id
where a.database_id = db_id()
order by a.avg_fragmentation_in_percent desc
When I rebuild an index the fragmentation does not change 10% or lower (default index fill factor is 0, which I think is 90% fill)
SQL Server 2005 EE SP 2
Thanks,
~Joseph~
Fragmentation Of SQL Data Files
Mar 30, 2004Hi,
How do you defragement SQL database data files? Running the DBCC DBREINDEX , DBCC INDEXDEFRAG, does that minimize fragmentations of the tables and the indexes files or is it just the index files?
Thanks in advance
a
Index Showing Fragmentation
May 11, 2015We have nightly job running to reorg all in one of our prod database. But the index on one of the table fragmenting quickly by the morning showing 90% fragmentation.
View 9 Replies View RelatedSQL Server Memory Fragmentation
Dec 7, 2006Abe writes "i am using SQL server 2000, when i tried to back up the database in SQL server, the backup began failing coz SQL Server could no longer allocate 964kb of contiguous blocks. (the min needed is 1MB)
What causes the memory or blockes to be fragmented?
How do you solve this issue other than rebooting the server?
How do you prevent this from happening or monitor this issue?
Regards,
Abe"
Logical Scan Fragmentation
Aug 16, 2007I have a table with 50% Logical Scan Fragmentation. [ according to Dbcc Showcontig (myTable) ]
Why after running DBCC INDEXDEFRAG (myDB,myTable) does it still sit at 50%.
Why isn't it lower?
Catch-22 With Fragmentation And Shrinking
Sep 10, 2007I've inherited a SQL 2005 Server with a major problem. It's been badly admin'd for ages.
It's got a 250gb disk with 3% space free. The disk is 93% fragmented. There is a sql data file of 231gb on that volume that i'm trying to shrink as it has 92gb of free space on it apparently. It won't shrink because the fragmentation is too bad - it just hangs for 2 days then times out. I've tried shrinking the files and database to no avail. I can't defrag as it just says it's finished after 2 minutes and doesn't do anything.
Any suggestions or am I screwed?
System Tables Fragmentation
Jul 20, 2005can you defrag system tables. They appear in my dbcc showcontigreport. Some are worse than other but if it where a user table Iwould defrag it. However the reindex commands doesnt work on systemtables.... Any ideas.Thanks Matt.
View 1 Replies View RelatedIndex Fragmentation Issue
Feb 9, 2008
Hi,
It is natural that index gets fragment overtime. But I would like to know how you do the reindexing or defragment when your database table is big and you cannot afford the time to rebuild them. Thanks.
Check Fragmentation Without DBCC
Nov 21, 2007Hi All,
I want to check the fragmentation for a table. But I do not have permissions to run DBCC commands on that server. Do we have any other method to identify the health of the table?
Thanks a lot.
Mannu.
Index Fragmentation On SQL 2000
Nov 8, 2007I have several databases in which our indexes have not been rebuilt/reorganized. I have worked primarily on SQL 2005 but with 2000 I am not familiar with Logical vs Extent fragmentation. And on the 2000 server there is high Logical Fragmentation (1000+%). With me rebuilding the indexes on the 2000 server databases, will this reduce performance or halt functionality of the servers while this process is running???
View 6 Replies View RelatedHow To Find Fragmentation Of Indexes
Mar 27, 2008Hi
I try to find the percentage of fragmentation in the perticular table using the following table. For some tables it is getting the results but for some database tables it is saying the error in qurey even if I use same query. Is there any reason for that. Or is there any other way to find out the fragmentation of table. any help would be fine. Thanks!
SELECT a.index_id, name, avg_fragmentation_in_percent
FROM sys.dm_db_index_physical_stats (DB_ID(), OBJECT_ID(N'schema.tablename),
NULL, NULL, NULL) AS a
JOIN sys.indexes AS b ON a.object_id = b.object_id AND a.index_id = b.index_id;
GO
And is there any way to find out when did index rebuild occurs in perticular index or table. Thank you very much.
SQL Server Table Size /Fragmentation
Jun 8, 2000Hi!,
I have a process(Peoplesoft) in SQL Server which takes long time to finish. I am looking for is there any way to find out fragmentation of the table to defagment it or is there any way to allocate the size for particular table. Couple of users are running the process at same time but as SQL Server has table/page locks it locks and releases after the job is done. Can i make it row level lock by executing sp_tableoption procedure. I would appreciate for all your suggeations.
Thanks,
Mohana
High Extent Scan Fragmentation
Oct 25, 2002Can anyone let me now why the extent scan fragmentation is very high.
I do have a clustered index on this table .
The fill factor is 0 and this table has high inserts as it is used to maintain history.
Rebuilding the Indexes did not help.
DBCC SHOWCONTIG scanning 'ACCOUNTS' table...
Table: 'ACCOUNTS'(1061578820); index ID: 1, database ID: 5
TABLE level scan performed.
- Pages Scanned................................: 728157
- Extents Scanned..............................: 91759
- Extent Switches..............................: 93305
- Avg. Pages per Extent........................: 7.9
- Scan Density .......: 97.55% [91020:93306]
- Logical Scan Fragmentation ..................: 0.33%
- Extent Scan Fragmentation ...................: 99.99%
- Avg. Bytes Free per Page.....................: 76.6
- Avg. Page Density (full).....................: 99.05%
DBCC execution completed. If DBCC printed error messages, contact your system administrator
Thanks in advance,
Shades[B]Extent Scan Fragmentation
SQL 2012 :: Cluster Index Fragmentation
Jun 2, 2014We have few tables where we do truncate load or only do insert activities , why do the cluster index get fragmented very often to > 80%?
View 9 Replies View RelatedIndexes Showing Fragmentation Percentage As 99%
Oct 20, 2015I have rebuilded indexes and some of the indexes still showing fragmentation percentage as 99%. I have cross checked page count for these indexes and they are more than 10000 pages.As i am aware if the page count is less we can ignore this percentage. But in my case the page count is 10000.
View 2 Replies View RelatedConclusive Fragmentation Evidence Required
Sep 5, 2007Currently managing a VLDB which is heavily fragmented. The applications characteristics are heavy INSERTS, UPDATES and DELETES and against my recommendations the majority of the large tables are HEAPS or have inadequate non-clustered indexes. The code is dynamic SQL, the tables dynamic and the vendor's understanding of SQL is poor which hampers my progress here.
Both the OS defrag GUI and sys.dm_db_index_physical_stats show huge amounts of fragmentation, some tables are around 80%. Note: (Indexreorg jobs are in place where indexes are present)
The problem I have is convincing the windows engineers whom contol the budget that deploying a defrag tool such as Idera's Defrag Manager will actually be of any use. They keep asking whether the app will actually will get inside the DB and I'm curious whether there will be any benefit on the HEAP tables should the vendor not make changes to their code.
Is there any conclusive evidence I can provide these Window guys to quantify my defrag expenditure request? Any help would be appreciated
Index Fragmentation Strategy For VLDB
Nov 20, 2007I need to manage the problem of negative performance implications when I fragment a 1TB+ DB. I want to perform Index Reorganization if fragmentation is no higher than 30%, and Index Rebuild if the fragmentation exceeds 30%.
Firstly can anyone recommend a script which uses sys.dm_db_index_physical_stats system to ascertain the
fragmentation level. Secondly, is there a technique I can employ to prevent the ONLINE operation completely killing performance on 27/4 production system?
ALTER INDEX REORGANIZE/REBUILD WITH (ONLINE=ON)
MDF Disk Fragmentation - Backup And Restore
Jul 23, 2005If databases on a physical drive [G:] are fragmented, and the drive isextended by adding more hard drives to the array, does it make sense tobackup and restore the fragmented databases?The Windows Server should be able to find contiguous space for eachdatabase, since it shows 75% free space on the SQL Data drive withoutany file fragments on it.Or will it restore to the original location, in which case does it makesense to delete the databases and restore them from the backups?Thank you very much!
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