I 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
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
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?
Hi,
I have a script to rebuild and reorganize indexes for sybase i.e reorg rebuild index... like command i have. Now i want similar command for MSSQLSqlserver.plz help me.
My index reorganise maintenance plan fails partly due to the disabled indexes
Executing the query "ALTER INDEX [I_ModelSecurityCommon_RECID] ON [dbo]...
" failed with the following error: "Cannot perform the specified operation on disabled index 'I_ModelSecurityCommon_RECID' on table 'dbo. Model SecurityCommon'.". Possible failure reasons: Problems with the query, "ResultSet" property not set correctly, parameters not set correctly, or connection not established correctly.
I don't want to delete the indexes as they are standard indexes that where on the DB from install.. any script that will reorganise all enabled indexes? and also to rebuild?
Hi 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
After 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?
I have a series of indexes that are showing as statistics. Is it because they are filtered or are defined as constraints?
View 5 Replies View RelatedWe 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?
I 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
Hi,
I am contemplating creating a job to execute every 5 mins which will update index statisics if they are more than say 8% out. I would like to know what thoughts people have on this? i.e. pros and cons.
I like forward to what you have to say.
I have auto stats on. Our stats are often more than 10% out. At what level do you reckon the query plan might be effected by out of data stats?
Thanks
Jamie.
Is the Update Statistics found in a Maintenance Plan performed online or offline? Will it kick users out when this is run on SQL Server 2000?
Thanks
Hi,
It seems to me there are many ways to update statistics for a table. i.e. "sp_updatestats", "sp_recompile", "dbcc updateusage"
Can somebody tell me the difference between those commands and what's the best way for updating your statistics? Does reindexing update the statistics?
thx,
Wilfred van Dijk
HI,
To update statistics for entire DB i have taken the script from under given link.But need to know the
1 : what is sample percent on update statistics
2 : will it be applicable for 2005 ?
script taken from :
http://weblogs.sqlteam.com/tarad/archive/2006/08/14/11194.aspx
kindly reply soon.
How do you schedule a weekly job to do "update statistics" thru all the databases?
View 6 Replies View RelatedHi All,
I update statistics for three tables every day 2:00 AM and in the job we call
one stored procedure and, in that stored procedure only three statements are
writtern for update statistics
Like:
Exec('update statistics TBL1 with fullscan')
Exec('update statistics TBL2 with fullscan')
Exec('update statistics TBL3 with fullscan')
And this job was working fine since many months but last two days its getting fail and it gives the error messages like :
could not continue scan with NOLOCK due to data movement
So could you help me what is the solution for this
Thanks,
Aric
Hi,
I would like to know when we upgrade SQL Server 2000 database to SQL Server 2005 is it required to update the statistics even if we rebuild all the indexes or create new indexes?
Thanks,
Ritesh
Hi,
I am planning to change our current UPDATE STATISTICS strategy, which is auto stats ON. Our database is terrabytes sizes and some tables with millions of rows with over 200 indexes in one table. Some of these indexes are not really used. Most of the tables are very small.
Droping and creating new indexes are quite often used in our environment. So static script may not help.
How can I identify most frequently used indexes in a table?
With the Microsft recommended auto stats ON, what are the best other practices I can include to improve the effeciency?
Any help would be apprecited. It would be realy great if any of you can share some scripts to generates dynamic scripts.
best regards
Priw
Hello,
Can "update statistics tablename" be run while the server is in multi-user mode and users accessing the table to be updated?????
Thanks in advance...
On a SQL 7 sp 2 server, I have a database with about about 77,000 records, with automatic update statistics on inserting 1000 records took 43 minutes. With automatic update off, it took 23 minutes to insert the same 1000 records. On the same machine, I inserted 1000 records into 2 other databases with the same database structure and automatic update statistics on. On the second database, there are about 174000 records and it took 35 minutes to insert 1000 records. On the third database, there are about 93000 records and it took 19 minutes to insert 1000 records.
Why is the time so high on the first database?
What can be done to fix the problem?
Thank you.
I have a query that retrieves a single record from searching on two tables.
The statement goes like this...
select sum(amount) from Table1 A union Table2 B on a.id = b.id
where date < ### and date > #### and account = ###
As people are running a particular report, this statement is executed time and
time again to pull up the numbers necesarry for the report. When the report gets slow, I can speed it up by updating the statistics. My concern is that I'm having to update the statistcs every hour; otherwise, the query becomes slow. I have noticed that users are inserting data while users are running the report on one of the tables listed above. I'm sure that's making it become more fragmented and ultimately slowing down the query.
Do you have any suggestion on how I can make the union of these two tables faster? Or is there anything I could do to speed the query besides creating clusted indexes?
Any help would be appreciated....thank you
I am maintaining a large table with millions of rows that has two non clustered indexes and data changing frequently, I need to keep the indexes fresh. Update Statistics runs much quicker than Reindex. What is the appropriate situation for each and why?
Thanks in advance.
Hi
We are upgrading from sql 7 to 2000.During the upgrade process do we have to do a reindexing of all tables or will update statistics take care of that.
Or do we have to do both?
What is the difference between reindexing and update statistics.
Thanks
Madhukar Gole
I have recently defragged my SQL server using INDEXDEFRAG. Can somebody please tell me how to update the statistics on all the tables? Thanks in advance.
Below is the script that I executed to defrag all the tables in my database if anyone needs this.
/*Perform a 'USE <database name>' to select the database in which to run the script.*/
-- Declare variables
SET NOCOUNT ON
DECLARE @tablename VARCHAR (128)
DECLARE @execstr VARCHAR (255)
DECLARE @objectid INT
DECLARE @indexid INT
DECLARE @frag DECIMAL
DECLARE @maxfrag DECIMAL
-- Decide on the maximum fragmentation to allow
SELECT @maxfrag = 20.0
-- Declare cursor
DECLARE tables CURSOR FOR
SELECT TABLE_NAME
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE'
-- Create the table
CREATE TABLE #fraglist (
ObjectName CHAR (255),
ObjectId INT,
IndexName CHAR (255),
IndexId INT,
Lvl INT,
CountPages INT,
CountRows INT,
MinRecSize INT,
MaxRecSize INT,
AvgRecSize INT,
ForRecCount INT,
Extents INT,
ExtentSwitches INT,
AvgFreeBytes INT,
AvgPageDensity INT,
ScanDensity DECIMAL,
BestCount INT,
ActualCount INT,
LogicalFrag DECIMAL,
ExtentFrag DECIMAL)
-- Open the cursor
OPEN tables
-- Loop through all the tables in the database
FETCH NEXT
FROM tables
INTO @tablename
WHILE @@FETCH_STATUS = 0
BEGIN
-- Do the showcontig of all indexes of the table
INSERT INTO #fraglist
EXEC ('DBCC SHOWCONTIG (''' + @tablename + ''')
WITH FAST, TABLERESULTS, ALL_INDEXES, NO_INFOMSGS')
FETCH NEXT
FROM tables
INTO @tablename
END
-- Close and deallocate the cursor
CLOSE tables
DEALLOCATE tables
-- Declare cursor for list of indexes to be defragged
DECLARE indexes CURSOR FOR
SELECT ObjectName, ObjectId, IndexId, LogicalFrag
FROM #fraglist
WHERE LogicalFrag >= @maxfrag
AND INDEXPROPERTY (ObjectId, IndexName, 'IndexDepth') > 0
-- Open the cursor
OPEN indexes
-- loop through the indexes
FETCH NEXT
FROM indexes
INTO @tablename, @objectid, @indexid, @frag
WHILE @@FETCH_STATUS = 0
BEGIN
PRINT 'Executing DBCC INDEXDEFRAG (0, ' + RTRIM(@tablename) + ',
' + RTRIM(@indexid) + ') - fragmentation currently '
+ RTRIM(CONVERT(varchar(15),@frag)) + '%'
SELECT @execstr = 'DBCC INDEXDEFRAG (0, ' + RTRIM(@objectid) + ',
' + RTRIM(@indexid) + ')'
EXEC (@execstr)
FETCH NEXT
FROM indexes
INTO @tablename, @objectid, @indexid, @frag
END
-- Close and deallocate the cursor
CLOSE indexes
DEALLOCATE indexes
-- Delete the temporary table
DROP TABLE #fraglist
GO
I am looking to run UPDATE STATISTICS for the first time, don't ask why it wasn't done prior please :(, on a set of large tables in our 346gb database whcih has been being populated with transactional data for the past 4 years. The tables contain 1.2, 35, 64, and 92 million rows. I have used the STAT_DATE function to determine that none of these tables have ever had update statistics run for them.
My question is how should I go about this process and what options should I be selecting when issuing the command? I assume that I must first run with the FULLSCAN paramater in order to initially generate statistics for the table then would assume that following this initial population I could run without any paramaters nightly against the tables in the database to keep statistics up to date. Any guideance you all could provide to a newb would be greatly appreciated.
Thanks! Scott Clark
Hi Gurus,
I need you update statistics on table .
Is there any command or stored procedure for this.
Thanks,
ServerTeam
Hi all,
I'm using SQL 7, there is a setting on DB properties called "Auto update statistics", what kind of statistics does this refers to and how can this stats be accessed?
Thanks for your help!
Gustavo
Thanks,
GS
Hi. I have automatic statistic update turned on for all my databases. Isthis an overhead I can do without? Could I update them overnight when thedatabase is hardly in use?Thanks--Chris Weston
View 1 Replies View RelatedI have Auto Create Statistics and Auto Update Statistics ON in one of my databases.
How do I know what time the Auto Update Statistics Kicks on ?
I dont see it in the log.
Is there a way for me to find out when was the last time Auto Update Statistics kicked on?
TIA
Hello
I have interesting situation with one of my update statement.
Update takes 2 min to run and usually updates 20000 rows.
However lately update executes for longest time - 10 hours.
After I reindex table the updates run fine again
Please advice what can cause this
I do not think reindexing table before every update is good idea
We are running SQL 2000 SP4, Windows 2003 Server
Thank you in advance for all your help
Armine
Hi all,
Is it neccessay to run the "Update Statistics" after run "DBCC DBReindex"? Does "Update Statistics" automatically update the stats?
Thanks in advance
Kim,
Hi all,
We are using SQL Server 2005. The auto update statistics and auto create statistics for a database is set to ON. This database has a very heavy work load. When I checked the individual statitics , still the last updated statistics is in a old date value (few months ago).
Is it necessary to manually update the statistics for the same database? Or can we rely upon "auto update statistics" itself ?
Usually in what frequency the manual UPDATE STATISTICS should be run on production system which has heavy transactions ?
Thanks & Regards,
Hariarul
Hi all ,
We had a SQL server (2005) that was performing very bad . We thought of doing an UPDATE STATISTICS thinking that the response times would increase.
BUT , UNFORTUNATELY THE SERVER PERFORMANCE BECAME WORSE FROM BAD.
Ex : Stored procedures that took 2 minutes are running for 22 minutes now. Queris that ran for 17 seconds are running for 14 minutes now.
Anybody faced this kind of issue earlier ? Any help would be appreciated.
Thanks & Regards,
Hariarul