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?
I 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] ....
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
Hi ..
Please advice whether i have to do update statistics along with Index rebuild (online /off line)
Thanks in advance
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.
Currently our database size is around 350G. It will grow up to 1.5 TB
We have the
Auto create statistics option :True,
auto update statistics option :True,
auto update statistics asynchronously option : False
at database level
we have a weekly job, update statistics running very long time. It is created through maintenance plan using the option full scan.
Previously they tested with sampling but instead of full scan running with the sampling effected the queries.
Is there option to avoid the long time job duration.
If we didn't run the statistics manually what will happen? How do you maintain statistics with large databases
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 are planning to standardize our newly deployed sql server, As a part of it we have configured 2 maintenance plans 1) Update Statistics which runs daily and 2) Index Reorganize which runs on weekly.
Apart from above, any other things to be in place for better maintenance of the sql server.
Also, how to Index Rebuild activity for clustered indexes requires any downtime.
I'm working on databases where statistics of some indexes (tables) are changing too frequently. Once I update them manually, one minute after they get 10-20% change, and five minutes after they get over 100% change. Tables get updated very frequently (multiple times in a second).
When I run a query to read from sys.stats, sys.dm_db_stats_properties and other dynamic views, I see that they were last updated when I did it manually, but the change rate overpassed the 500+20% (tables have multiples of 10K rows). Auto create and update statistics are set to true on all databases, and I don't know why sql server does not do that automatically.
Hi All.
Our inhouse app used to run on a SQL2000, but we've recently moved it to 2005.
The move was done by way of backup and restore (it was on a whole new server).
After the move, an odd problem showed up: once in a while, the server seems incapable of finding/using its indexes: everything starts working slowly, until I run a maintenance plan that rebuilds its indexes etc.
In the database/server all relevant options seem to be ok (auto update statictiscs etc.), and my conclusion that it doesn't use its indexes comes from the fact that:
* it gives the results from certain select statements in a totally different order (although the set of rows is the same),
* performance is (all of a sudden) very slow (seconds turning to minutes!!)
This happens:
* at least after a reboot of the server
* sometimes just in the middle of the day
The only way I've found to solve the matter, is by running the maintenance plan to rebuild the indexes, but sometimes this only seems to work the second time.
Does anybody share this experience, or know what to do about it?
Thanks,
Nick.
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
When creating the snapshot I didn't choose the option copy non-clustered indexes. I created some indexes manually on subscriber database. Replication failed later with some issue.
so reinitialized with new snapshot but all the indexes are gone from the subscriber database.
How to keep the indexes without dropping from subscriber database whenever we reinitialized with snapshot
I written a proc to display the list of Indexes But I needed to print the database where the objects do belong to. How I should write the Dynamic script to add the database Id? I thought to use derived table kind of stuff, but unable to find a solution.
ALTER PROC [dbo].[USP_INDEXCHECK]
AS
DECLARE @sql NVARCHAR(max)
DECLARE @DB VARCHAR(max)
DECLARE databasecursor CURSOR FOR
[Code] .....
Do I need to rebuild my indexes on my High Availability listeners?
When I do a full index rebuild on my primary DB's. Does rebuilding also send the rebuild to the listener(s)?
I have a query, I am trying to update a certain column in my query you can see that is hard coded. The column that I am trying to update is "O_Test" I used a select statement trying to figure out how many records that accounts for with the entire database of all the tables. I got 643 records. So I am wondering if there is a way I can update all the columns without looking up each table and updating each one. This Update statement wont work because I am accounting for all records in the DB of all tables associated of what I hard coded
SELECT t.name AS table_name,
SCHEMA_NAME(schema_id) AS schema_name,
c.name AS column_name
FROM sys.tables AS t
INNER JOIN sys.columns c ON t.OBJECT_ID = c.OBJECT_ID
WHERE c.name LIKE '%O_Test%'
ORDER BY schema_name, table_name;
Hi
I had run a stored procedure in my server that update statistics against all user defined tables in my database (MSSQL 7.0).
Since then I am getting errors in my ASP application where I am reffering to adovbs.inc.
Here is an example of errors I get.
Microsoft VBScript runtime error '800a0411'
Name redefined: 'adOpenForwardOnly'
/Essai/adovbs.inc, line 14
Below is the stored procedure I have run against the database.
Can anybody help tank you guys.
CREATE PROCEDURE update_all_stats
AS
/*
This PROCEDURE will run UPDATE STATISTICS against
ALL user-defined tables within this database.
*/
DECLARE @tablename varchar(30)
DECLARE @tablename_header varchar(75)
DECLARE tnames_cursor CURSOR FOR SELECT name FROM sysobjects
WHERE type = 'U'
OPEN tnames_cursor
FETCH NEXT FROM tnames_cursor INTO @tablename
WHILE (@@fetch_status <> -1)
BEGIN
IF (@@fetch_status <> -2)
BEGIN
SELECT @tablename_header = "Updating " +
RTRIM(UPPER(@tablename))
PRINT @tablename_header
EXEC ("UPDATE STATISTICS " + @tablename )
END
FETCH NEXT FROM tnames_cursor INTO @tablename
END
PRINT " "
PRINT " "
SELECT @tablename_header = "************* NO MORE TABLES" +
" *************"
PRINT @tablename_header
PRINT " "
PRINT "Statistics have been updated FOR ALL tables."
DEALLOCATE tnames_cursor
Hi All,
SQL 7 REQUIRES THE DBA TO MANAGE THE INDEXES AND IN PARTICULAR THE FILL FACTOR AVAILABILITY. DOES SQL SERVER 2000 AUTOMATICALLY ADDRESS THIS OR DO WE STILL HAVE TO PERIODICALLY RUN,
sp_MSforeachtable @command1="print '?' DBCC DBREINDEX ('?')"
TO REBUILD ALL INDEXES IN THE DATABASE?
Thanks in advance,
-Praveena
Hi!
I'm not a dba at all, just a simple developer but I have got the assignment to help out with performance problems on a db.
I noticed that almost all indexes are fragmented 75-99%. Can I rebuild them when the database is in use? Can I reorganize indexes when the db is used?
/Magnus
Jesus saves. But Gretzky slaps in the rebound.
In the maintance plans there is a Rebuild Index choice.
If u choose tables and views the plan executes
ALTER INDEX <index> ON <table> ;REBUILD
for all indexes in the datebase.
I am currently using this plan on our production DB, scheduled for every Saturday night.
I wonder if there is a downside of using maintance plans. Because it seems to be doing the job. Any comments?
I am upgrading from SQL2000 to SQL2005.
I have restored my 2000 db to 2005.
I have changed the Compatiblilty level to 90.
Now I need to reindex.
How do I reindex all the tables at once?
Thanks for ALL your help
r/p
how can run a command to rebuild all indexes in a database?
I had to to relocate the database log file and I issued an Alter database command but by mistake I put a space in the file name as below. The space is at the beginning file name. Now I am unable get the database loaded to SQL Server. The database has 2 replications configured, so deleting and re-attaching the database means the replication needs to be re-configured. Is there an alternative way to issue a command to update the database FILENAME ? Not sure if this can be edited in master database (sys files).
ALTER DATABASE [User_DB]
MODIFY FILE (NAME = User_DB_log, FILENAME = 'I:SQLLogs User_DB_log.ldf')
GO
So 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?
We have a script running everyday for rebuild and re-organisation of indexes. But, somehow its getting failed. Attached script for your consideration. There is no database name with amoperations. There is table called DatabaseObjectAudit but it exist on master db.
Message:
-->Start Index Maint
-> Gathering fragmentation information (can take a while!)
-> Gathering COMPLETE : Total of 43 databases were found.
-> Gathering COMPLETE : Total of 1622 indexes were found.
[code]...
I have a number of databases that are being transactionally replicated from SQL 2000 Enterprise edition publisher to SQL 2005 Enterprise edition subscriber. I have included indexes in the replication. The subscriber database is then accessed and the data de-normalised and aggregated for reporting purposes.
My question is this: I want to periodically re-build the indexes on the publisher and subscriber via an automated task. If I rebuild the indexes on the publisher, will that automatically replicate to the subscriber? Will there be a problem with the "snapshot being out of date", and therefore replication stopping? I run a new snapshot once a day in the small hours of the morning. If there is likely to be a problem with the rebuild throwing the replication out, would it be wise to have the rebuild job running just before the new snapshot is taken?
Any help/advice appreciated.
MS SQL 2008.I want to execute a delete query on certain tables in my database to delete some rows in the tables.The tables selected has a certain name pattern (the name ends with "Temp").
So I can do this to get a list of the table names
SELECT name
FROM sys.Tables where
name like '%Temp'
Now I want to check each table to see if it has a column with the name "DateStamp" and then execute a delete query as follows:
delete form TableName where
DateStamp is < '2010-01-01'
In other words I need to iterate through the tables names, How to do this?
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 RelatedHi,
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.
I am using SQL Server 2008 (RTM) Standard Edition.
In my environment, one of my Database size is 75 gb and I have to create a plan for index rebuild using maintenance plan.But when we rebuild indexes, it requires some space on data and log files of database.how can we calculate disk space requirement for index rebuild process ?
i would like to know it's possible to find all transaction(insert, delete,update) on a database for a day. if yes what can i do.
View 2 Replies View RelatedWe have a maintenance plan running everyday for rebuild and re-organisation of indexes. But, somehow its getting failed. Here is the script that we are running for rebuild or re-org.
/*
Script to handle index maintenance
Tuning constants are set in-line current values are;
SET @MinFragmentation
SET @MaxFragmentation
SET @TrivialPageCount
[code]....