DB Design :: Indexes Showing Up As Statistics?
Jul 15, 2015I have a series of indexes that are showing as statistics. Is it because they are filtered or are defined as constraints?
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Reorganize Indexes/Update Statistics
Jun 29, 2000I am using the Maintencance Plan wizard, but it only allows me to either select the "reorganize data and indexes" option or the "update statistics" option (in the Optimizations tab). I can't select both of them. What is the reason for this?
joe
Auto Create Statistics / Indexes
Sep 1, 2000Hi everyone,
I know that statistics called _WA_... are created on tables when auto create statistics is set on a database. Is this an indication that queries against the table would perform better if indexes were created on the columns in question? (The tables I'm interested in optimising are used equally for transactional querying and reporting)
Thanks for any replies!
Les
Stealth Indexes & Statistics Recompute
Jul 26, 1999After our upgrade and migration from v6.5 to v7.0, there are new indexes shown on the sysindexes table. All of these new indexes have names that start with the characters '_WA_Sys_'.
Before the upgrade, one database had 88 indexes but now it has 643. One table went from 1 index to 92.
The systems person who did the install and upgrade believes that these new objects only appear to be indexes, and that they are statistics that are automatically generated to aid in performance.
a) Does anyone else have these?
b) What are they?
c) Where can I read about them?
d) Could they cause performance slowdown?
Indexes 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 RelatedSQL Server 2008 :: Update Statistics On Tables Of Database After Rebuild Indexes?
Nov 5, 2015If 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?
DB Design :: Log Shipping Alert Job Showing Error 14220
Jun 3, 2015my database is already deleted and there  is no job are running for  that database .previously we configure a log shipping for that database  and deleted.log shipping backup job also deleted.the log shipping alert job is throwing bellow error.
The log shipping primary database tes1 has backup threshold of 60 minutes and has not performed a backup log operation for 132722 minutes. Check agent log and logshipping monitor information.
Indexes Design
Feb 17, 2005If I have a table with Col1 + Col2 as PK. But most of the queries use Col1, Col2, Col3 and Col4 in the queries, should I create another unique index on this combination? If not, my queries do an index scan. Just wondering is there a general rule for this kind of situation as I have a lot of such cases in my database.
View 13 Replies View RelatedDB Design :: Rebuilding Clustered Indexes
Jul 23, 2015Currently we are facing some performance issue while accessing the archive data from the archive tables. the archive table is hugh and it contains around 100,000,000 records and this archive table is being used in few reports and in our commission cycles too. since we are facing performance issues we are rebuilding index once in a week on all the indexes on this archive table.
We have 1 clustered index and 5 non clustered indexes, every time when we rebuild all these indexes on this table it is taking more time, more often rebuilding the clustered index itself is taking approx. 1hr which is consuming more time. wanted to know is there any useful to rebuild clustered indexes or not, if yes then what would be the better way. if not then do we need to rebuild only non clustered indexes.
Implementaion Of Datamining And Design Aform For Showing The Result Of Prediction With Time Series
Nov 26, 2007 hi
i have aques tion about mining model and time series after predicting
how can i show the result of the prediction in the c# form
and why i cant use the all of the prediction function in the mining
model prediction for time series and how i can see the script of the
building mining model in the model because i can see just the wizard
of the model and how can i undrestand othe about time series formula
in the chart
thanks alot if answer me
DB Design :: Optimizing Merge Statement By The Use Of Indexes On Target
Nov 13, 2015This website describes how Merge statements should be optimized by the use of indexes on the target?source tables: [URL]..... It says that a clustered index should be created on the join column in the target and a unique covering index on the source table.Â
I have read in other articles that insert/delete/update statements perform worse on tables with clustered indexes as the leaf level pages will have to be reorganized.
Why in the case of Merge statement having a indexes actually improve the performance of insert/delete/update statements?
DB Design :: Need To Recreate All Indexes From Primary To Secondary File Group
Jul 14, 2015I have a database around 500 GB. right now the database have only one data file and one log, it has only one filegroup also.all the indexes and table are placed in Primary Filegroup . we are going to separate them. the planing is to move all the indexes to Secondary filegroup and all the table will be in Primary filegroup.But there will be a problem while implementing it because there are around 600 tables and each table have at least 2 non-clustered index , so is there any way to move all the index to Secondary Filegroup.
View 3 Replies View RelatedAuto Created Statistics And Missing Statistics
Jul 20, 2005Hello group.I have an issue, which has bothered me for a while now:I'm wondering why the column statistics, which SQL Server wants me tocreate, if I turn off auto-created statistics, are so important to theoptimizer?Example: from Northwind (with auto create stats off), I do the following:SELECT * FROM Customers WHERE Country = 'Sweden'My query plan show a clustered index scan, which is expected - no indexexists for Country. BUT, the query plan also shows, that the optimizer ismissing a statistic on Country, which tells me, that the optimizer wouldbenefit from knowing this.I cannot see why? (and I've been trying for a while now).If I create the missing statistics, nothing happens in the query plan (andwhy should it?). I could understand it, if the optimizer suggested an indexon Country - this would make sense, but if creating the missing index, queryanalyzer creates the statistics with an empty index, which seems to me to beless than usable.I've been thinking long and hard about this, but haven't been able to reacha conclusion :) It has some relevance to my work, because allowing theoptimizer to create missing statistics limits my options for designingindexes (e.g. covering) for some rather wide tables, so I'm thinking why notturn it off altogether. But I would like to know the consequences - hopesomebody has already delved into this, and knows a good explanation.RgdsJesper
View 5 Replies View RelatedUnit Of Time-statistics In Client Statistics
Aug 1, 2006What is the unit of the numbers you get in the Time Statistics-part when running a query in Microsoft SQL Server Management Studio with Client Statistics turned on?
Currently I get mostly 0´s, but if I try and *** up a query on purpose I can get
it up to around 30... Is it milliseconds or som made up number based on clockcycles or... ?
I would also like to know if it´s possible to change the precision.
- Nikolaj
Removal Of Selected Indexes / Script Index Create For List Of Indexes
Jul 1, 2014I'm working to improve performance on a database I've inherited, and there are several thousand indexes. I've got a list of ones which should definitely exist within the database, and I'm looking to strip out all the others and start fresh, though this list is still quite large (1000 or so).
Is there a way I can remove all the indexes that are not in my list without too much trouble? I.e. without having to manually go through them all individually. The list is currently in a csv file.
I'm looking to either automate the removal of indexes not in the list, or possibly to generate the Create statements for the indexes on the list and simply remove all indexes and then run these statements.
As an aside, when trying to list all indexes in the database, I've found various scripts to do this, but found they all seem to produce differing results. What is the best script to list all indexes?
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?
SQL 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] ....
Indexes Vs Clustered Indexes
Sep 17, 2006What is the difference please?
View 1 Replies View RelatedDB Design :: Database Design For Matrix Representation
May 13, 2015I have a scenario like below
Product1
Product2 Product3
Product4 Product5
Product1 1
1 0 0
1
Product2 1
1 0 0
1
Product3 0
0 1 1
0
Product4 0
0 1 1
0
Product5 1
1 0 0
1
How to design tables in SQL Server for the above.
Database Design/query Design
Feb 13, 2002Ok, I'm doing a football database for fixtures and stuff. The problem I am having is that in a fixture, there is both a home, and an away team. The tables as a result are something like this:
-------
Fixture
-------
fix_id
fix_date
fix_played
----
Team
----
tem_id
tem_name
-----------
TeamFixture
-----------
fix_id
tem_id
homeorawayteam
goals
It's not exactly like that, but you get the point. The question is, can I do a fixture query which results in one record per fixture, showing both teams details. The first in a hometeam field and the second in an away team field.
Fixture contains the details about the fixture like date and fixture id and has it been played
Team contains team info like team id, name, associated graphic
TeamFixture is the table which links the fixture to it's home and away team.
TeamFixture exists to prevent a many to many type relationship.
Make sense? Sorry if this turns out to be really easy, just can't get my head around it at the mo!
DB Design :: Table Design For Packages
Aug 18, 2015I would like to create a table called product. My objective is to get list of packages available for each product in data grid view column while selecting each product. Each product may have different packages type (eg:- Nos, CTN, OTR etc). Some product may have two packages and some for 3 packages etc. Quantity in each packages also may be differ ( for eg:- for some CTN may contain 12 nos or in other case 8 nos etc). Prices for each packages also will be different that also need to show. Â How to design the table..Â
Product name  : Â
Nestle milk |
Rainbow milk
packages  :
CTN,OTR, NOs |
CTN, NOs
Price:
50,20,5 |
40,6
(Remarks for your reference):CTN=10nos, OTR=4 nos Â
| CTN=8 Nos
Statistics
Jul 31, 2000I need a script to drop all statistics in a database at once.
HELP!
Statistics
Jun 14, 2001I want to be able to generate a script that gives me all statistics that are in my database currently.
Does anyone know how to do this? Is the following correct:
select --a.id as SysIndex_id,
'create statistics ' + a.name + ' on ' + b.name + ' (' + SUBSTRING(A.NAME, 9, LEN(A.NAME)-17) + ')'
as SysIndex_name
--b.name
from
sysindexes A left join sysobjects B
on A.id = B.id
where a.name like '%wa%'
order by b.name
Where, Oh Where, Have My Little Statistics Gone?
Aug 3, 2007Hi all,
As part of my automagical nightly index maintenance application, I am seeing a fairly regular (3-4 failures out of 5 attempts per week) failure on one particular table in my database. The particular line which seems to be failing is this one:
DBCC SHOWCONTIG (WON_Staging_EPSEst) WITH FAST, TABLERESULTS, ALL_INDEXES
The log reports the following transgression(s):Msg 2767, Sev 16: Could not locate statistics 'WON_Staging_EpsEst' in the system catalogs. [SQLSTATE 42000]
Msg 0, Sev 16: [SQLSTATE 01000]
Msg 0, Sev 16: -------------------- Simple ReIndex for [WON_Staging_EpsEst].[IX_WON_Staging_EpsEst] [SQLSTATE 01000]
Msg 2528, Sev 16: DBCC execution completed. If DBCC printed error messages, contact your system administrator. [SQLSTATE 01000]
Msg 0, Sev 16: [SQLSTATE 01000]
Msg 0, Sev 16: -------------------- Post-Maintenance Statistics Report for WON_Staging_EpsEst [SQLSTATE 01000]
Msg 0, Sev 16: Statistics for WON_Staging_EpsEst, WON_Staging_EpsEst [SQLSTATE 01000]
Msg 2528, Sev 16: DBCC execution completed. If DBCC printed error messages, contact your system administrator. [SQLSTATE 01000]
Msg 0, Sev 16: Statistics for WON_Staging_EpsEst, IX_WON_Staging_EpsEst [SQLSTATE 01000]
Msg 2768, Sev 16: Statistics for INDEX 'IX_WON_Staging_EpsEst'. [SQLSTATE 01000]
Updated Rows Rows Sampled Steps Density Average key length
-------------------- -------------------- -------------------- ------ ------------------------ ------------------------
Aug 3 2007 3:22AM 674609 674609 196 2.0958368E-4 8.0
(1 rows(s) affected)
This table is dropped and recreated each day during a data import job. After the table is recreated and repopulated with data (using a bulk import from a flat file), the index is also recreated using the following code:CREATE INDEX [IX_WON_Staging_EpsEst]
ON [dbo].[WON_Staging_EpsEst](OSID, [Year], Period)
ON [PRIMARY]Yet more often than not, that evening, when the index maintenance job runs, it fails with the aforepasted messages complaining of being unable to find table/index statistics.
Worth noting, perhaps, is that this same process is used on roughly 10 data staging tables in this database each day, and none of the other tables fail during the index maintenance job.
Also worth noting, perhaps, is that this IDENTICAL table/code is processed in exactly the same way on TWO other servers, and the failure has not occured in any of the jobs on those other two servers (these other two servers are identical mirrors of the one failing, and contain all the same data, indicies, and everything else.
Any thoughts, suggestions for where to look, or unrestrained abusive comments regarding my ancestry?
Thanks!
Statistics
Jun 13, 2008I have a small doubt.
If we apply a statistics command on a particular table what will it update.
Normally statistics are created automatically by the server or we have to create it.
SQL Use Statistics
Jul 20, 2005Anybody know how many companies worldwide use SQL server and how manyindividual servers this amounts to? Also, at what rate is SQL usegrowing? Can someone at least point me to a source where I could findclose to exact numbers?
View 2 Replies View RelatedA Statistics Question
Jun 20, 2001Here my data sample on which I need to perform some stats
Time(Sec) Result
1 2
2 8
3 6
4 2
5 2
6 4
7 2
8 7
9 8
What I need from this is a result set that looks as follows
GroupNo Value
1 5.33
2 2.67
3 5.67
This is a grouping of the result data in 3's by time. Value is the average of the Group.
In need to write a select statement to do this.
Note the Group could be done from 1 to 10
The end result of this is to display a Range Chart which shows Results grouped according to requirements.
Any Help would nice.
Pargat
Statistics On Tables
Oct 10, 2001Hello List,
I would like to know, How can I drop Statistics from tables. My user tables has two indexes and and some statistics created onto them. I would like to drop the statistics indexes and apprecaite, If someone please advice.
The statistics indexes looks something like this:
"_WA_Sys_status_01EAB64E"
Any help would be apprecaited.
Thanks,
Index Statistics
Jun 6, 2000What 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
Dropping The Statistics
Nov 17, 2000Does anyone have any generic scripts that Drop all the statistics that SQL auto generates?? I have hundreds of '_WA_....'
indicies that are auto created by SS7 and I just want to get rid of ALL of them. Thanks!
Index Statistics
Feb 14, 2001I 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 RelatedCreate Statistics
Jun 14, 2000When the "create statistics" command is run, what table entries are made into system tables?
I want to check for the existence of statistics on certain columns and if they are not there, create them. What is a good way to see if they are already created?
Update Statistics
Feb 6, 2001I am using SQL 6.5. We have tables of upto 2.5GB in size. Running update statistics againts these tables takes too long, and locks out users.
Anyone know how I can make this quicker?
Davy