How Do I Tell When To Rebuild A Clustered Index?
Sep 20, 2007
How do I tell when to rebuild a clustered index and what is the best way to do so?
Thanks!
Michael
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Big Clustered Index Rebuild
Jul 25, 2007I 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
Rebuild Clustered Index On 500 Million Row Table???
Jan 17, 2008My environment is SQL 2000. I have a table with 500 million rows. The table is consistently getting updated and inserted. I can not take the table offline. My clustered index needs to be rebuilt due to decreased performance. How do I accomplish this?
View 7 Replies View RelatedSQL Server 2008 :: Logic To Rebuild Only Clustered Indexes / Skipping To Rebuild Non Clustered Indexes In Same Table
Jun 25, 2015I have a requirement to only rebuild the Clustered Indexes in the table ignoring the non clustered indexes as those are taken care of by the Clustered indexes.
In order to do that, I have taken the records based on the fragmentation %.
But unable to come up with a logic to only consider rebuilding the clustered indexes in the table.
create table #fragmentation
(
FragIndexId BigInt Identity(1,1),
--IDENTITY(int, 1, 1) AS FragIndexId,
DBNAME nvarchar(4000),
TableName nvarchar(4000),
[Code] ....
Simple Query Chooses Clustered Index Scan Instead Of Clustered Index Seek
Nov 14, 2006the query:
SELECT a.AssetGuid, a.Name, a.LocationGuid
FROM Asset a WHERE a.AssociationGuid IN (
SELECT ada.DataAssociationGuid FROM AssociationDataAssociation ada
WHERE ada.AssociationGuid = '568B40AD-5133-4237-9F3C-F8EA9D472662')
takes 30-60 seconds to run on my machine, due to a clustered index scan on our an index on asset [about half a million rows]. For this particular association less than 50 rows are returned.
expanding the inner select into a list of guids the query runs instantly:
SELECT a.AssetGuid, a.Name, a.LocationGuid
FROM Asset a WHERE a.AssociationGuid IN (
'0F9C1654-9FAC-45FC-9997-5EBDAD21A4B4',
'52C616C0-C4C5-45F4-B691-7FA83462CA34',
'C95A6669-D6D1-460A-BC2F-C0F6756A234D')
It runs instantly because of doing a clustered index seek [on the same index as the previous query] instead of a scan. The index in question IX_Asset_AssociationGuid is a nonclustered index on Asset.AssociationGuid.
The tables involved:
Asset, represents an asset. Primary key is AssetGuid, there is an index/FK on Asset.AssociationGuid. The asset table has 28 columns or so...
Association, kind of like a place, associations exist in a tree where one association can contain any number of child associations. Each association has a ParentAssociationGuid pointing to its parent. Only leaf associations contain assets.
AssociationDataAssociation, a table consisting of two columns, AssociationGuid, DataAssociationGuid. This is a table used to quickly find leaf associations [DataAssociationGuid] beneath a particular association [AssociationGuid]. In the above case the inner select () returns 3 rows.
I'd include .sqlplan files or screenshots, but I don't see a way to attach them.
I understand I can specify to use the index manually [and this also runs instantly], but for such a simple query it is peculiar it is necesscary. This is the query with the index specified manually:
SELECT a.AssetGuid, a.Name, a.LocationGuid
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')
To repeat/clarify my question, why might this not be doing a clustered index seek with the first query?
A Question About Clustered Indexes Forcing Rebuild Of Non-clustered Indexes.
Sep 18, 2007So I'm reading http://www.sql-server-performance.com/tips/clustered_indexes_p2.aspx and I come across this:
When selecting a column to base your clustered index on, try to avoid columns that are frequently updated. Every time that a column used for a clustered index is modified, all of the non-clustered indexes must also be updated, creating additional overhead. [6.5, 7.0, 2000, 2005] Updated 3-5-2004
Does this mean if I have say a table called Item with a clustered index on a column in it called itemaddeddate, and several non-clustered indexes associated with that table, that if a record gets modified and it's itemaddeddate value changes, that ALL my indexes on that table will get rebuilt? Or is it referring to the table structure changing?
If so does this "pseudocode" example also cause this to occur:
sqlstring="select * from item where itemid=12345"
rs.open sqlstring, etc, etc, etc
rs.Fields("ItemName")="My New Item Name"
rs.Fields("ItemPrice")=1.00
rs.Update
Note I didn't explicitly change the value of rs.fields("ItemAddedDate")...does rs.Fields("ItemAddedDate")=rs.Fields("ItemAddedDate") occur implicitly, which would force the rebuild of all the non-clustered indexes?
DB Engine :: How To Convert Unique Clustered Index Into Clustered Primary Key To Use With Change Tracking
Sep 4, 2015We 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.
View 4 Replies View RelatedDB Design :: Script To Create Table With Primary Key Non-clustered And Clustered Index
Aug 28, 2015I desire to have a clustered index on a column other than the Primary Key. I have a few junction tables that I may want to alter, create table, or ...
I have practiced with an example table that is not really a junction table. It is just a table I decided to use for practice. When I execute the script, it seems to do everything I expect. For instance, there are not any constraints but there are indexes. The PK is the correct column.
CREATE TABLE [dbo].[tblNotificationMgr](
[NotificationMgrKey] [int] IDENTITY(1,1) NOT NULL,
[ContactKey] [int] NOT NULL,
[EventTypeEnum] [tinyint] NOT NULL,
[code]....
Data Warehousing :: Difference Between Primary Key With Clustered And Non-clustered Index
Jul 19, 2013I have created two tables. table one has the following fields,
Id -> unique clustered index.
table two has the following fields,
Tid -> unique clustered index
Id -> foreign key of table one(id).
Now I have created primary key for the table one column 'id'. It's created as "nonclustered, unique, primary key located on PRIMARY". Primary key create clustered index default. since unique clustered index existed in table one, it has created "Nonclustered primary key".
My Question is, What is the difference between "clustered, unique, primary key" and "nonclustered, unique, primary key"? Is there any performance impact between these?
Create Clustered Or Non-clustered Index On Large Table ( SQL Server 7 )
Jan 4, 2008I have large table with 10million records. I would like to create clustered or non-clustered index.
What is the quick way to create? I have tried once and it took more than 10 min.
please help.
Integration Services :: Rebuild Index / Refresh Index And Stats Improves Ssis Package Performance
Oct 28, 2015My 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 RelatedConverting A Clustered Index On A PK Identity Field To Non-clustered
Sep 8, 2006Hi there, I have a table that has an IDENTITY column and it is the PK of this table. By default SQL Server creates a unique clustered index on the PK, but this isn't what I wanted. I want to make a regular unique index on the column so I can make a clustered index on a different column.
If I try to uncheck the Clustered index option in EM I get a dialog that says "Cannot convert a clustered index to a nonclustered index using the DROP_EXISTING option.". If I simply try to delete the index I get the following "An explicit DROP INDEX is not allowed on index 'index name'. It is being used for PRIMARY KEY constraint enforcement.
So do I have to drop the PK constraint now? How does that affect all the tables that have FK relationships to this table?
Thanks
Include Clustered Index In Non-clustered Index?
Oct 15, 2007Hi 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.
Right? Wrong? Keep the column in the index, or remove it since it is included implicit anyway?
Thanks for suggestions!
Ralf
Clustered Index On Client_ID+ORderNO+OrdersubNo, If I Create 3 Noncluster Index On Said Column Will It Imporve Performance
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.
The always search by OrderID, or ClientID or order_SubNo, or enter any two like (Client_ID+Order_Sub_ID) or any combination.
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:-
Q1. IF Person "A" query to DB on Client_ID, then what Index will use ? (If any one do Query on any two combination like Client_ID+Order_ID, So what index will be uesd.? How does MS-SQL SERVER deal with these kind of issues.?
Q2. If i create 3 more indexes on ClientID, ORderID and OrdersubID. will this improve the performance of query.if person "A" search record on orderNo so what index will be used. (Mind it their would be 3 seprate indexes for Each PK columns) and composite-Clustered index is also available.?
Q3. I want to check what indexes has been used? on what search?
Q4. How can i check what table was populated when, or last date of update (DML)?
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
Clustered And Non Clustered Index On Same Columns
Nov 1, 2007I have a table<table1> with 804668 records primary on table1(col1,col2,col3,col4)
Have created non-clustered index on <table1>(col2,col3,col4),to solve a performance issue.(which is a join involving another table with 1.2 million records).Seems to be working great.
I want to know whether this will slow down,insert and update on the <table1>?
Reorganize Index And Rebuild Index ??
Mar 18, 2008Hi,
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
Reorganize Index And Rebuild Index
Mar 18, 2008Hi,
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
Advantages Of Using Nonclustered Index After Using Clustered Index On One Table
Jul 3, 2006Hi everyone,
When we create a clustered index firstly, and then is it advantageous to create another index which is nonclustered ??
In my opinion, yes it is. Because, since we use clustered index first, our rows are sorted and so while using nonclustered index on this data file, finding adress of the record on this sorted data is really easier than finding adress of the record on unsorted data, is not it ??
Thanks
SQL 2012 :: Clustered Index Key Order In NC Index
Mar 5, 2015I have a clustered index that consists of 3 int columns in this order: DateKey, LocationKey, ItemKey (there are many other columns in this data warehouse table such as quantities, prices, etc.).
Now I want to add a non-clustered index on just one of the other columns, say LocationKey, like this:
CREATE INDEX IX_test on TableName (LocationKey)
I understand that the clustered index keys will also be added as key columns to any NC indexes. So, in this case the NC index will also get the other two columns from the clustered index added as key columns. But, in what order will they be added?
Will the resulting index keys on this new NC index effectively be:
LocationKey, DateKey, ItemKey
OR
LocationKey, ItemKey, DateKey
Do the clustering keys get added to a NC index in the same order as they are defined in the clustered index?
Clustered Index Vs. Full Text Index
Jun 18, 2008Quick question about the primary purpose of Full Text Index vs. Clustered Index.
The Full Text Index has the purpose of being accessible outside of the database so users can query the tables and columns it needs while being linked to other databases and tables within the SQL Server instance.
Is the Full Text Index similar to the global variable in programming where the scope lies outside of the tables and database itself?
I understand the clustered index is created for each table and most likely accessed within the user schema who have access to the database.
Is this correct?
I am kind of confused on why you would use full text index as opposed to clustered index.
Thank you
Goldmember
Index Rebuild Took 9 Hrs
Jun 29, 2001Running 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
Index Rebuild
Nov 1, 2006Hi All,
Is there any way to calculate how big the transaction log will grow during the rebuilding of the indexes?
Thanks.
Index Rebuild
Jan 11, 2006I 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
Jan 15, 2008Rebuild 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?
Speeding Up An Index Rebuild....
Dec 19, 2000Hi 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!
Alter Index ... Rebuild
May 1, 2008If 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 RelatedIndex Rebuild Does Not Defrag
Oct 3, 2007Hi,
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...
Nov 16, 2007Does "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
Index Rebuild Question
Nov 6, 2007
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?
Rebuild And Reorganized Index
Jan 18, 2008assuming 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
Transact SQL :: Index Rebuild MP
Oct 12, 2015I 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 RelatedMsg 2511 / Rebuild Index Not Working
Jun 23, 1999Fellow MSSQL DBA's, I am stuck. I am getting a Msg 2511 on a production database. The message reads - Table Corrupt: Keys in leaf page should be in ascending order. I have dropped the offending index and rebuilt both through the application and through ISQL. Neither method fixed the problem. DBCC CHECKDB shows no errors as long as the index does not exist. I have checked out the data and see no problems. Any ideas?
Thanks very much.
Tracy Hughes
thughes@neonsoft.com
office 303-805-5693
Rebuild Index Task - Online Only?
Jun 19, 2008Hi 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