Online Index Rebuild And Update Statistics
Dec 12, 2006Hi ..
Please advice whether i have to do update statistics along with Index rebuild (online /off line)
Thanks in advance
Hi ..
Please advice whether i have to do update statistics along with Index rebuild (online /off line)
Thanks in advance
Is it neccessary to schedule a update statistics on index in sql server 2005 on daily basis
Is it neccessary to schedule a rebuild index on index in sql server 2005 on daily basis
At one of your client sides we have configured Always on with synchronous mode.Also we have schedule rebuild index and update statistics job which runs in night every alternate day. the issue is there are more then 100 sleeping queries which is blocking update statistics job.
I have to stop update statistics job manually once i come to office manually.
Once I have killed blocking sleeping query but then other sleeping query blocked it and so on.
Hi all,
In SQL Server 2005 EE I created a maintenance plan to rebuild indexes for a few large tables. I have selected five specific tables, and I'm using both "sort results in tempdb" as well as "keep index online while reindexing".
If I execute this plan for all these tables, are the indexes guaranteed to remain online? There are all different types of indexes on these tables. For example, the table "Contacts" has 8 indexes: 1 Clustered, 1 PK Unique Non-Clustered, 2 Unique Non-Clustered, and 4 Non-Unique Non-Clustered. I've heard that only certain types of indexes can remain online during a reindex (Clustered and Non-Unique Non-Clustered??).
Will SQL Server rebuild an index that isn't compatible with the online reindex mode, or will it choose to ignore it?
Thanks,
- Matt
I'm running SQL Server 2008 R2 with latest patch. I'm performing all index maintenance online. How long the final phase of the index operation takes? Does the size of the index matter and if any blocking occurs, does the duration increase because the size of indexes is larger? I've been told by management, we can not have any downtime, its my understanding even with online index there's a chance blocking can occur in the final phase of the index operation. My database and index size is over 1.5 tb and the number of transaction per second are in the 100's.
View 2 Replies View RelatedTable A
5.6GB
80 million rows
Initial Page Space Used = 85.7% (sys.dm_db_index_physical_stats - avg_page_space_used_in_percent)
Index and data size are almost unchanged after an ONLINE rebuild of the clustered index. Page count actually goes up by 800. No fill factor or pad index settings. Page space used = 99.2%
During an OFFLINE rebuild the page count drops by ~20%. Page space used = 99.8%.
How can the pages be 99.2% used yet the number of pages hasn't gone done from the ONLINE rebuild?
I'm getting the feeling a shortcut was taken somewhere. Does an ONLINE rebuild only reorganize leaf level index pages but not any of the upper levels? Essentially it puts the pages in order but doesn't do any structure consolidation like OFFLINE?
It would seem that you're missing out on some of the benefits of defragmenting if your data is still spread across more pages and you don't get as many rows per read or it takes more reads to go down your tree to get to your data.
I do a lot of index maintenance and started testing rebuilding my indexes with the ONLINE option, but noticed an increase in record size by 14 bytes. The issue I have is that for each index you build the ONLINE option, you add 14 bytes for row. After the index rebuild is done, normal transaction updates drop the additional 14 bytes.
The act of adding and dropping 14 bytes would cause fragmentation and uncompressed data. Is this correct or do I have something wrong?
I have a very large table with approximately 400 million records in it. Every 10 seconds approximately 150 insert are done on the table. I am attempting to rebuild one of the indexes (non-unique, non-clustered). But when I run a script to rebuild the index online (i have enterprise edition) the VB.NET service that is attempting to insert generates SQL timeout errors (timeout set to 30 seconds). From an article on msdn they state that long term table locks are not held for the duration of the index operation. So what am I missing because I am not close to being a DBA. I know SQL Server is not a SCADA but it is not my choice.
Here is the script for one of the rebuilds
USE [DATABASENAME]
GO
ALTER INDEX [IX_REALLY_BIG_TABLE_DT]
ON [dbo].[REALLY_BIG_TABLE] REBUILD
WITH ( PAD_INDEX = OFF,
STATISTICS_NORECOMPUTE = OFF,
ALLOW_ROW_LOCKS = OFF,
ALLOW_PAGE_LOCKS = ON,
SORT_IN_TEMPDB = OFF,
ONLINE = ON )
GO
Here is the article
http://msdn.microsoft.com/en-us/library/ms188388.aspx
We use below OLA script to do our index maintenance and one of our previous engineer designed below script on web edition and I have a question of how online index rebuild works when we have web edition. Does the online Index rebuild really works? I am thinking it only reorganizes and does not do online index rebuild.
sqlcmd -E -S $(ESCAPE_SQUOTE(SRVR)) -d master -Q "
EXECUTE [dbo].[IndexOptimize] @Databases = 'DBName1',
@FragmentationLow = NULL,
@FragmentationMedium = 'INDEX_REORGANIZE,INDEX_REBUILD_ONLINE',
@FragmentationHigh = 'INDEX_REORGANIZE,INDEX_REBUILD_ONLINE',
@FragmentationLevel1 = 5,
@FragmentationLevel2 = 30,
@LogToTable = 'Y'" -b
If I rebuild some indexes that are above 30% of average fragmentation, should I after that update statistics?
Also, How can I see if I Need to update statistics^on the tables of my database?
We have a 20 GB database and reorganize indexes and update statistics maintainance takes about 4 hours and the log files grows out of control what is a serious problem since it can not be truncated (database mirroring).
Ivan
I have a job that runs nightly, rebuild index. job runs fine every night but every few weeks it fails.
USE msdb
GO
EXECUTE dbo.IndexOptimize
@Databases = 'USER_DATABASES',
@FragmentationLow = NULL,
@FragmentationMedium = 'INDEX_REORGANIZE,INDEX_REBUILD_ONLINE,INDEX_REBUILD_OFFLINE',
@FragmentationHigh = 'INDEX_REBUILD_ONLINE,INDEX_REBUILD_OFFLINE',
@FragmentationLevel1 = 5,
@FragmentationLevel2 = 30,
@SortInTempdb = 'Y',
@UpdateStatistics = 'ALL',
@OnlyModifiedStatistics = 'Y'
This calls the Sp that does the Reindex. It fails at the update statistics with a very generic message. like " Command: UPDATE STATISTICS [xxxx_DB].[dbo].[xxxx_xxx] [_WA_Sys_00000007_49C3F6B7] [SQ... The step failed."
I suspect it has more error but this is all it is showing me when I right click on the job history. therefore, I updated the job step in the advance tab with log to a txt file. Am I on the right track or there is another way to see error some where else.
I looked at the logs but they didn't show any thing.
We face slow performance issue for like taking long time for same query execution after We apply index rebuild and reorganize index. But, after execution of query or procedure for 2 -3 times, performance will be faster. I have following questions
1 do we need to update stats after we rebuild an reorganize index.
2. is it will be slow for 1-2 times for every query and stored procedure execution after we rebuild and reorganize index?
My SSIS package is running very slow taking so much time to execute, One task is taking 2hr for inserting 100k records, i have disabled unused index still it is taking time.I am rebuilding/Refreshing indexes and stats once in month if i try to execute on daily basis will it improve my SSIS Package performance?
View 2 Replies View RelatedHi,
I just want to know whether any advantage or disadvantage
in doing Reorganize Index And Rebuild Index ....
Plz do comment on this ASAP !!!!
Thanks in advance
Regards
Arv
Hi,
I just want to know whether any advantage or disadvantage
in doing Reorganize Index And Rebuild Index ....
Plz do comment on this ASAP !!!!
Thanks in advance
Regards
Arv
Running SQL 7.0 SP3 on P3 dual 800.
I rebuild indexes every night as part of the maintenance plan. Usually it takes about 1 hr 10 minutes on a 15 G db, last night it took 9 hrs.
I have no idea why it would take so long. Nothing changed, there were no new indexes created and none deleted.
Any ideas? I have to find out why. My boss wants an answer.
Thanks in advance.
Kelsey
Hi All,
Is there any way to calculate how big the transaction log will grow during the rebuilding of the indexes?
Thanks.
I run dbcc dbreindex command and send the output to the text file. Is there any other way to check that indexes were in fact rebuild?
View 1 Replies View RelatedRebuild Index job for user db's is failing, one user db is a huge size 120 GB. The job scheduled to run every sunday 1 AM
I found the below error in log report
Rebuild Index Task (server name)
Rebuild index on Local server connection
Databases: All user databases
Object: Tables and views
Original amount of free space
Task start: 01/13/2008 1:26 AM.
Task end: 01/13/2008 2:38 AM.
Failed-1073548784) Executing the query "ALTER INDEX [Idx_CISCO_WLC_EVENTID] ON [dbo].[CISCO_WLC_200711262137] REBUILD WITH ( PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON, SORT_IN_TEMPDB = OFF, ONLINE = OFF )
" failed with the following error: "Cannot find the object "dbo.CISCO_WLC_200711262137" because it does not exist or you do not have permissions.". Possible failure reasons: Problems with the query, "ResultSet" property not set correctly, parameters not set correctly, or connection not established correctly.
Please let me know the solution?
Hi all...
I have a table with over 60 million rows (approx 20GB) which has an indexed column. I have tried using DBC DBReindex to rebuild the index, but after kicking it off on a friday, it is still running the following wednesday. Since managers and other finicky types access this database, that's not acceptable (it slows down their reporting).
Is there a way to speed up the reindexing process? Perhaps by adding space to the tempdb (it's 500MB) or putting it in RAM temporarily? I haven't seen any articles that specifically state that TEMPDB is used during an index rebuild, but it seems logical that it would be.
Any suggestions to speed up the process would be most appreciated!
If the index to be rebuilt is a clustered index, will all non-clustered indexes be rebuilt also by rebuilding only the clustered index.
View 7 Replies View RelatedAnyone using the ONLINE=ON option on large DB's? We have a db of 5 GB and we are doing some load testing for SQL 2005. We are modifying the Index scripts for the upgrade. We will run a load with the ONLINE=ON option but just wanted to find out if anyone already is doing it on a similar scale db and has seen any issues?
Also, we have auto-update stats off at the DB level. Does setting the ONLINE=ON require turning this auto-update stats to ON too? I didnt see anything to that effect in BOL, so was wondering.
Thanks for any feedback.
Dinakar Nethi
SQL Server MVP
************************
Life is short. Enjoy it.
************************
http://weblogs.sqlteam.com/dinakar/
Hi,
After issuing an index rebuild on a primary key index (and updating statistics), the index still shows a scan density of 12.5%!
Any ideas on why the rebuild doesn't seem to do anything on the fragmentation levels?
I'm using sql 2005
Thanx
Does "Alter Index All Rebuild" rebuild just the tree level of the index? Or does it also rebuild the leaf level like reorganize?
Thanks and God Bless,
Thomas
ThomBeaux
So, I was under the impression that with the online index feature in SQL 2005 would prevent blocking if DML statements occur on the underlying table. I tried to rebuild the indexes on one of our tables that has a lot of traffic, and it caused a ton of blocking statements. Would anyone have any ideas why this would occur?
View 3 Replies View Related
How do I tell when to rebuild a clustered index and what is the best way to do so?
Thanks!
Michael
If I rebuild an index using:
ALTER INDEX IndexName ON dbo.TableName REBUILD WITH (ONLINE = ON)
Why would dm_db_index_physical_stats, show avg_fragmentation_in_percent as 50 percent?
assuming that i don't have a problem that rebuilding the index take more CPU and locks the database resources.
if i run the rebuild index ,do i need to run the reorganized index as well? or the rebuild index fix whats the reorganizes Will fix if it will run?
THX
I would like to completely understand the difference between index rebuild Maintenace plan and the customized script.Maintenance Plan rebuilds every single index.It will take the long time as it checks every index.If we use a custom script as a job, it will rebuild the index which has fragmentation >30%.So that, the job will not take much time.
View 11 Replies View RelatedI need to establish the storage requirements for a clustered index rebuild with SQL 05. The table is made up of the following columns
[ProductID] [int] NOT NULL,
[RegionID] [int] NOT NULL,
[TimeID] [int] NOT NULL,
[FactID] [int] NOT NULL,
[Value] [decimal](14, 4) NOT NULL
This is the clustered index :-
[RegionId] ASC,
[FactId] ASC,
[TimeId] ASC,
[ProductId] ASC
This is the result of a sp_spaceused on this particular table
name
rows
reserved
data
index_size
unused
Table
16910379278
868107368 KB
863579184 KB
3869848 KB
658336 KB
The database where this table is stored is in Simple recovery mode.
What i would really like to know is, what additional storage would i require to run the following rebuild index command.
Alter Index blah on table Rebuild
Thanks
What are some ways to analyze index coverage and usage? I have a 18 GB database, half is data, other half is indexes and I want to cut down that number as much as I can without affecting performance. Thanks
Peter Karhatsu
I have been monitoring some indexes on a table with a lot of inserts, no updates and no deletes. I was wanting to determine when to update the statistics on the index. Does anyone know what would be a good target range for the density when you run the dbcc show_statistics?
View 1 Replies View Related