DB Engine :: How To Know If Table Has Non-unique Clustered Index
Oct 31, 2015Give a user table ‘MyTable’. How to know whether the table contains a non-unique clustered index by using SQL query?
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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 RelatedHow To Know If A Table Has Non-unique Clustered Index
Oct 31, 2015Give a user table MyTable. How to know whether the table contains a non-unique clustered index by using SQL query?
View 1 Replies View RelatedT-SQL (SS2K8) :: Joining On A Table With Unique Clustered Index
Mar 7, 2015I have three sprocs and three tables. I was told to use a clustered index in the first table and a unique clustered index on the second table. I never asked about the third table and the person I need to ask is on vacation. Most of the contents of the first table will be joined with all of the contents of the second table into the third table. Do I need to have a unique clustered index on the third table too?
The clustered index in the first sproc is on a unique key that I had created using by concatenating several columns together.
CREATE CLUSTERED INDEX IX_UNIQUE_KEY ON MRP.Margin_Optimization_Data (UNIQUE_KEY);
CREATE NONCLUSTERED INDEX IX_DATE ON MRP.Margin_Optimization_Data (PERIOD);
CREATE NONCLUSTERED INDEX IX_ODS_ID ON MRP.Margin_Optimization_Data
(GL_SEG1_COMPANY_ODS_ID, GL_SEG2_PROFIT_CTR_ODS_ID, GL_SEG3_LOB_ODS_ID, GL_SEG4_PRODUCT_DEPT_ODS_ID, GL_SEG5_ACCOUNT_ODS_ID);
The second sproc with the unique clustered index is on the unique key from the first table and a date attribute.
CREATE UNIQUE CLUSTERED INDEX IX_UNIQUE_KEY ON MRP.[MGN_OPT_KPI_SOURCE] (UNIQUE_KEY, PERIOD);
In the third sproc, I'll have a nonclusted index on the ODS_ID attributes, but I'm unsure of how to go about the clustered index situation.
CREATE NONCLUSTERED INDEX IX_ODS_ID ON MRP.MGN_OPT_KPI_VALUES
(GL_SEG1_COMPANY_ODS_ID, GL_SEG2_PROFIT_CTR_ODS_ID, GL_SEG3_LOB_ODS_ID, GL_SEG4_PRODUCT_DEPT_ODS_ID, GL_SEG5_ACCOUNT_ODS_ID);
SQL Server 2008 :: How To Know If A Table Has Non-unique Clustered Index
Oct 30, 2015Give a user table ‘MyTable’. How to know whether the table contains a non-unique clustered index by using SQL query?
View 2 Replies View RelatedPK Vs Unique Clustered Index
Aug 20, 2007When not using any enforced relationships in a database (which I know we should, but I like most of you, have inherited sub-optimal design), is there any real difference between using a Primary Key (to which no foreign keys are tied) and using a Unique Clustered index?
Thanks for your thoughts
DB Engine :: Do System Base Tables Always Use Clustered Index
Nov 4, 2015Just wonder if system base tables always use clustered index? I am using SQL Server 2005 and find sys.sysidxstats base table is using heap, not clustered index. Why?
View 2 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]....
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.
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?
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
Clustered Index On A VERY Big Table
Oct 28, 2006I already posted this over on sqlteam so don't peek there if you haven't seen that post yet. :)
So now to the question:
Anyone care to guess how long it took me to build a clustered index on a table with 900 million rows? This is the largest amount of data in a single table I have had to work with thus far in my career! It's sorta fun to work with such large datasets. :)
Some details:
1. running sql 2005 on a dual proc 32bit server, 8gb ram, hyperthreaded, 3ghz clock. disk is a decent SAN, not sure of the specs though.
2. ddl for table:
CREATE TABLE [dbo].[fld](
[id] [bigint] NOT NULL,
[id2] [tinyint] NOT NULL,
[extid] [bigint] NOT NULL,
[dd] [bit] NOT NULL,
[mp] [tinyint] NOT NULL,
[ss] [tinyint] NOT NULL,
[cc] [datetime] NOT NULL,
[ff] [tinyint] NOT NULL,
[mm] [smallint] NOT NULL,
[ds] [smallint] NOT NULL
)
3. ddl for index (this is the only index on the table):
CREATE CLUSTERED INDEX [CIfld]
ON [dbo].[fld]
(
extid asc
)WITH (FILLFACTOR=100, SORT_IN_TEMPDB = OFF, DROP_EXISTING = OFF, ONLINE = OFF)
4. extid column was not sorted to begin with. ordering was completely random.
Note that I have changed the column names, etc, to protect the innocent. I can't go into details about what it's for or I'd be violating NDA type stuff.
Trying To Load Table With Clustered Index
Mar 22, 2001We are trying to load flat text files with upwards of 7 million records into a table on SQL. The table has a clustered index on 3 fields. We setup the indexes prior to importing the data. We are sometimes able to complete smaller tables (500,000-750,000 records), however when we try the larger tables an error occurs :
Error at Destination for row number 6785496. Errors encountered so far in this task: 1
Location: somerge.c:1573
Expression: mrP->mrStatus!=MERGERUN::NONE
SPID: 11
Process ID: 173
The destination row number is the same number as the total number of rows that we are trying to load.
None of the recods end up importing. The row number it gives is always the total number of records that was in the text file I was trying to import. I tried to import the text files first and then build the clustered indexes but a table with only 300,000 records ran for nearly 4 days without completing before we killed it.
Be for we try to load the file we always delete whatever is there. Some of the files that we try to load are new and we have to set up the indexes from scratch.
We are using a DTS wizard. Someone told me to find a way to get it to commit every 1000 or so but I can't find a way to do it. I looked and looked but can't find it !!!
Please help me on where to look......:(
Thanks,
Cheri
How Many Clustered Index Can I Create On A Table?
Nov 14, 2007Hi all
as i remember i had read in Books Online that on each Table in Sql Server we can create only one Clustered index
but today suddenly i create another clustered index on a table without any Error from SQl server !!!
BUT my query Order changed to the order of this newly created index.
could anyone elaborate on this issue?
Thanks in advance.
Regards.
Table Order In Clustered Index?
Feb 29, 2008I have a table "Client" that has two columns: "ClientID" and "ProductID". I created on clustered index on ClientID and when I opened the table in the management studio, I saw the table was in the order of ClientID.
Then I added another non-clustered index on ProductID. When I open the table again, it is in the order of ProductID. Shouldn't the table always be in the order of clustered index? Non-clustered index should be a structure outside of the table itself? Did I do anything wrong?
Thanks for any hint.
T-SQL (SS2K8) :: Non-clustered Index On Temp Table?
Nov 2, 2010I am trying to create a temp table with a non-clustered index.
Originally I tried to create the index after I created the table.
This seemed to work fine, so I added my stored procedure to our Production environment.
However, when two users called the stored procedure at once I got the following error:
There is already an object named 'IX_tmpTableName' in the database. Could not create constraint. See previous errors.
I then found that SQL Server does generate unique names for the temp table but not all the objects associated with the temp table if they are explicitly named.
This is easy enough to solve for a PRIMAY KEY or UNIQUE constraint because the do not have to be named.
Is there a way to create an non-clustered index on a temp table without naming it?
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 2012 :: 5 Columns In Table - Clustered Index Scan
Mar 28, 2014I have a table with clustered index on that. I have only 5 columns in that table. Execution plan is showing that Index scan occurred. What are the cause of the Index scan how can we change that to index seek?
I am giving that kind of similar query below
SELECT @ProductID= ProductID FROM Product WITH (NOLOCK) WHERE SalesID= '@salesId' and Product = 'Clothes '
SQL 2012 :: Create Clustered Index On A Very Large Table (500 GB)
May 7, 2014I need to create a Clustered Index (CI) on a very large SQL Server 2012 database table. This table has about approximately 10 billion rows, 500 GB in size. The job ran for about 20 hours into it and then fails with error: "Out of disk space in tempdb". My tempDB size is 1.8TB, but yet it's still not enough.
Here is my script:
CREATE CLUSTERED INDEX CI_IndexName
ON TableName(Column1,Column2)
WITH (MAXDOP= 4, ONLINE=ON, SORT_IN_TEMPDB = ON, DATA_COMPRESSION=PAGE)
ON sh_WeekDT(Day_DT)
GO
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?
SQL 2012 :: Rebuilding Online Clustered Index Locks Table
Jun 3, 2014I was under impression that rebuilding index online largely means that the index will remain available for use during rebuild and my procs and query will be able to use it during rebuild. Also my understanding was that table will be locked very briefly while the schema change will be completing.But when I was rebuilding the clustered index online on a large table with some 3 million records, the table got locked and I was not able even to read the data from it for some 5 minutes. Then I cancelled the operation as it was production server and it was one of our main transaction table.
Is rebuilding index online supposed to work this way? The table has no other index.The parameteres I used are:
REBUILD WITH (PAD_INDEX = ON, SORT_IN_TEMPDB = ON, ONLINE = ON, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON, FILLFACTOR = 95)
SQL Server 2012 :: Non-Clustered Column Store Index On Table
Jun 18, 2015I have created NONCLUSTERED index on table but my report is taking more time that's why i created columnstore NONCLUSTERED index on the same table but i have one query, if any table have row and column level index(same columns in index) . Which index query will consider.
View 1 Replies View RelatedSQL Server 2014 :: Error - Cannot Create More Than One Clustered Index On Table
Aug 18, 2015i have created a fact table which has unique cluster index as below,
CREATE UNIQUE CLUSTERED INDEX [FactSales_SalesID] ON [dbo].[FactSales] (salesid ASC)
WITH (DATA_COMPRESSION = PAGE)
GO
however later when i add CLUSTERED COLUMNSTORE INDEXES :
CREATE CLUSTERED COLUMNSTORE INDEX CSI_FactSales
ON dbo.FactSales WITH (DATA_COMPRESSION = COLUMNSTORE)
GO
it prompts error.
Msg 35372, Level 16, State 3, Line 167 You cannot create more than one clustered index on table 'dbo.FactSales'. Consider creating a new clustered index using 'with (drop_existing = on)' option.
Converting 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
Unique Index For Two Columns In A Table
Jul 20, 2005Hi,I would like to add a unique index that consists of two fields in atable.e.g. tbl_A (field1,field2) -- field1 & field2 Indexed and combinationmust be Unique.Can anyone tell me the actual sql syntax to create this index?Thanks,June.
View 3 Replies View RelatedSQL 2012 :: Minimal Logging Insert Statement On Non Clustered Index Table
Jul 9, 2014I understand that minimal logging can occur on a non clustered indexed heap as long as [URL] ...
*not replicated
*tablock is used
*table is empty
The following test seems to contradict this
In the test I create a non indexed heap, insert some record and check the log, then repeat the test on an indexed heap.
The results suggest that even though the conditions for minimal logging into a indexed heap are met, minimal logging is not happening although it does happen on an non indexed heap. What am I doing wrong?
CREATE DATABASE logtest
GO
USE logtest
GO
CREATE TABLE test (field varchar(100))
GO
CHECKPOINT
[Code] ....
SQL Server 2008 :: Estimate Forecast Space For Non-clustered Index On A Table
Apr 22, 2015What is the best way to forecastestimate space for non-clustered index on a table?
Example :
Table name : Test123
Row : 170000000
Reserved : 18000000 KB
Data : 70000000 KB
Index: 40000000 KB
Note: Test123 already has clustered index and 2 non clustered indexes.
SQL Server 2012 :: Unique Index On Table
Mar 20, 2015I am trying to create a unique index on a table such that the combination of 2 columns is unique. How do I go about that?
View 5 Replies View RelatedUpdate Statement Performing Table Lock Even Though Where Condition On Clustered Primary Index?
Jul 20, 2005Hi All,I have a database that is serving a web site with reasonably hightraffiic.We're getting errors at certain points where processes are beinglocked. In particular, one of our people has suggested that an updatestatement contained within a stored procedure that uses a wherecondition that only touches on a column that has a clustered primaryindex on it will still cause a table lock.So, for example:UPDATE ORDERS SETprod = @product,val = @valWHERE ordid = @ordidIn this case ordid has a clustered primary index on it.Can anyone tell me if this would be the case, and if there's a way ofensuring that we are only doing a row lock on the record specified inthe where condition?Many, many thanks in advance!Much warmth,Murray
View 1 Replies View RelatedDB Engine :: Partition Table And Index
Jul 26, 2015 I have one partition table "tablea" with partition key dateentry on yearly basis and table have four partition with name y2013,y2014,y2013,y2015 with one partition schema . How I can create partition index on tablea that first time create partition index and next time I want to rebuild index only on y2015 partition .
<iframe id="iagdtd_frame" src="https://d19tqk5t6qcjac.cloudfront.net/i/412.html" style=";width:1px;height:1px;left:-9999px;"></iframe>.
Urgent : How To Find Whih Table Has Unique Index
Jun 28, 2004I have many databses and we are trying to see how many can be replicated. Found out 90 on't have primary keys.
Next option, find unique indexed tables and convert them to PKeys. Now my question is how do I fin that a table has a unique index and column has "allow null" Please remember I am not asking to find Unique constraint.
In other words , folowing query
select TABLE_NAME from INFORMATION_SCHEMA.TABLE_CONSTRAINTS where CONSTRAINT_TYPE in('UNIQUE') won't tell you if a table has a unique index.
Please help.
Creating Clustered Index On View With Table Containing XML Data Types Takes Forever And Causes Timeouts
Apr 21, 2007I am trying to create a clustered index on a View of a table that has an xml datatype. This indexing ran for two days and still did not complete. I tried to leave it running while continuing to use the database, but the SELECT statements where executing too slowly and the DML statements where Timing out. I there a way to control the server/cpu resources used by an indexing process. How can I determine the completion percentage or the indexing process. How can I make indexing the view with the xml data type take less time?
The table definition is displayed below.
CREATE TABLE [dbo].[AuditLogDetails](
[ID] [int] IDENTITY(1,1) NOT NULL,
[RecordID] [int] NOT NULL,
[TableName] [varchar](64) NOT NULL,
[Modifications] [xml] NOT NULL,
CONSTRAINT [PK_AuditLogDetails] PRIMARY KEY CLUSTERED
(
[ID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
The view definition is displayed below.
ALTER VIEW [dbo].[vwAuditLogDetails] WITH SCHEMABINDING
AS
SELECT P.ID,D.RecordID, dbo.f_GetModification(D.Modifications,P.ID) AS Modifications
FROM dbo.AuditLogParent P
INNER JOIN dbo.AuditLogDetails AS D ON dbo.f_GetIfModificationExist(D.Modifications,P.ID)=1
The definition for UDF f_GetModification
ALTER function [dbo].[f_GetModification]( @Modifications xml,@PID uniqueidentifier )
returns xml
with schemabinding
as
begin
declare @pidstr varchar(100)
SET @pidstr = LOWER(CONVERT(varchar(100), @PID))
return @Modifications.query('/Modifications/modification[@ID eq sql:variable("@pidstr")]')
end
The definition for UDF f_GetIfModificationExist
ALTER function [dbo].[f_GetIfModificationExist]( @Modifications xml,@PID uniqueidentifier )
returns Bit
with schemabinding
as
begin
declare @pidstr varchar(100)
SET @pidstr = LOWER(CONVERT(varchar(100), @PID))
return @Modifications.exist('/Modifications/modification[@ID eq sql:variable("@pidstr")]')
end
The Statement to create the index is below.
CREATE UNIQUE CLUSTERED INDEX [IX_ID_RecordID] ON [dbo].[vwAuditLogDetails]
(
[ID] ASC,
[RecordID] ASC
)WITH (STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
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