Anyone using the ONLINE=ON option on large DB's? We have a db of 5 GB and we are doing some load testing for SQL 2005. We are modifying the Index scripts for the upgrade. We will run a load with the ONLINE=ON option but just wanted to find out if anyone already is doing it on a similar scale db and has seen any issues?
Also, we have auto-update stats off at the DB level. Does setting the ONLINE=ON require turning this auto-update stats to ON too? I didnt see anything to that effect in BOL, so was wondering.
Thanks for any feedback.
Dinakar Nethi
SQL Server MVP
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Life is short. Enjoy it.
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http://weblogs.sqlteam.com/dinakar/
So, I was under the impression that with the online index feature in SQL 2005 would prevent blocking if DML statements occur on the underlying table. I tried to rebuild the indexes on one of our tables that has a lot of traffic, and it caused a ton of blocking statements. Would anyone have any ideas why this would occur?
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?
I'm running SQL Server 2008 R2 with latest patch. I'm performing all index maintenance online. How long the final phase of the index operation takes? Does the size of the index matter and if any blocking occurs, does the duration increase because the size of indexes is larger? I've been told by management, we can not have any downtime, its my understanding even with online index there's a chance blocking can occur in the final phase of the index operation. My database and index size is over 1.5 tb and the number of transaction per second are in the 100's.
Table A 5.6GB 80 million rows Initial Page Space Used = 85.7% (sys.dm_db_index_physical_stats - avg_page_space_used_in_percent)
Index and data size are almost unchanged after an ONLINE rebuild of the clustered index. Page count actually goes up by 800. No fill factor or pad index settings. Page space used = 99.2%
During an OFFLINE rebuild the page count drops by ~20%. Page space used = 99.8%.
How can the pages be 99.2% used yet the number of pages hasn't gone done from the ONLINE rebuild?
I'm getting the feeling a shortcut was taken somewhere. Does an ONLINE rebuild only reorganize leaf level index pages but not any of the upper levels? Essentially it puts the pages in order but doesn't do any structure consolidation like OFFLINE?
It would seem that you're missing out on some of the benefits of defragmenting if your data is still spread across more pages and you don't get as many rows per read or it takes more reads to go down your tree to get to your data.
I do a lot of index maintenance and started testing rebuilding my indexes with the ONLINE option, but noticed an increase in record size by 14 bytes. The issue I have is that for each index you build the ONLINE option, you add 14 bytes for row. After the index rebuild is done, normal transaction updates drop the additional 14 bytes.
The act of adding and dropping 14 bytes would cause fragmentation and uncompressed data. Is this correct or do I have something wrong?
I have a very large table with approximately 400 million records in it. Every 10 seconds approximately 150 insert are done on the table. I am attempting to rebuild one of the indexes (non-unique, non-clustered). But when I run a script to rebuild the index online (i have enterprise edition) the VB.NET service that is attempting to insert generates SQL timeout errors (timeout set to 30 seconds). From an article on msdn they state that long term table locks are not held for the duration of the index operation. So what am I missing because I am not close to being a DBA. I know SQL Server is not a SCADA but it is not my choice.
Here is the script for one of the rebuilds USE [DATABASENAME] GO ALTER INDEX [IX_REALLY_BIG_TABLE_DT] ON [dbo].[REALLY_BIG_TABLE] REBUILD WITH ( PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, ALLOW_ROW_LOCKS = OFF, ALLOW_PAGE_LOCKS = ON, SORT_IN_TEMPDB = OFF, ONLINE = ON ) GO
Here is the article http://msdn.microsoft.com/en-us/library/ms188388.aspx
I have Enterprise version of SQL Server 2012 & SQL server 2008. I understand that Image/Text/NText is obsoleted and should not be used. That being said I dont understand why I couldnt rebuild the following clustered index, while I could with nonclustered index, this happens on both SQL 2008 and 2012. Here are the DDL.
CREATE TABLE [dbo].[Demo]( [ID] [int] NOT NULL, [FK_ID] [uniqueidentifier] NOT NULL, [SomeColumn] [nvarchar](100) NOT NULL, [Image] [image] NULL ) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
[code]...
An online operation cannot be performed for index 'IX1_Demo' because the index contains column 'Image' of data type text, ntext, image or FILESTREAM. For a non-clustered index, the column could be an include column of the index. For a clustered index, the column could be any column of the table. If DROP_EXISTING is used, the column could be part of a new or old index. The operation must be performed offline.
--Online rebuild works fine on non clustered index ALTER INDEX IX2_Demo ON Demo REBUILD WITH(ONLINE = ON)--It seems to me that some how having the Image datatype column in the table is an issue. eventhough that column is not part of the index.
We use below OLA script to do our index maintenance and one of our previous engineer designed below script on web edition and I have a question of how online index rebuild works when we have web edition. Does the online Index rebuild really works? I am thinking it only reorganizes and does not do online index rebuild.
I 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)
We have SQL cluster installed on top of windows cluster on VM environment. Node1 and Node2 under Windows Failover Cluster. SQL instance is currently on node2 the instance is up and running, but SQL Cluster service remains online pending and it restarts the instance on every 5 minutes.
SQL Browser service are running successfully.TCP/IP ports are enabled and configured.If we start the SQL server agent it is on for seconds and stopped immediately .Cluster Service is attempt to connect to the SQL service every few minutes (setting in SQL cluster resource) for the IsAlive check, if this fails then the SQL resource is restarted even if the instance was online. Hope this is what happening exactly.
[sqsrvres] ODBC Error: [08001] [Microsoft][SQL Server Native Client 11.0]SQL Server Network Interfaces: Error Locating Server/Instance Specified [xFFFFFFFF]. (268435455) 00001024.00053314::2015/10/30-19:57:50.772 ERR [RES] SQL Server <SQL Server (SIMAH_COMMDB)>: [sqsrvres] ODBC Error: [HYT00] [Microsoft][SQL Server Native Client 11.0]Login timeout expired (0) 00001024.00053314::2015/10/30-19:57:50.772 ERR [RES] SQL Server <SQL Server (SIMAH_COMMDB)>: [sqsrvres] ODBC Error: [08001] [Microsoft][SQL Server
Native Client 11.0]A network-related or instance-specific error has occurred while establishing a connection to SQL Server. Server is not found or not accessible. Check if instance name is correct and if SQL Server is configured to allow remote connections. For more information see SQL Server Books
Online. (268435455) 00001024.00053314::2015/10/30-19:57:50.772 INFO [RES] SQL Server <SQL Server (SIMAH_COMMDB)>: [sqsrvres] Could not connect to SQL Server (rc -1
SQL Server 7/2000: We have reasonably large tables (3,000,000 rows)that we need to add some indexes for. In a test, it took over 12 hoursto CREATE a new INDEX against this table. One of us suggested that wecreate a temp table with the new index and copy the data from the oldtable into the new one, then rename it. I understand this took 15minutes. Why the heck would it be faster to move the data and buildmultiple indexes incrementally vs adding an index??
What is the best procedure/sequence to reduce some tables containing large number of rows of a SQL 2000 server? The idea is first to check which tables grow extremely fast (all statistics, user or log tables), reduce the table according to the number of months the user wishes to keep in the table. As a second step backup remaining rows of table as txt files on harddisk (using DTS), UPDATE STATISTICS and re-indexing reduced table. Run DTS Package every month once (delete oldest month and backup newest month) and do the same as above to keep size of tables adequate. What is a fast way to reduce number of rows of a large table - the following example produces an error (timeout expired) of my ADO connection when executing: SET @str = 'DELETE FROM ' + @ProcessTable + ' WHERE ' + @SelectedColumn + ' < DATEADD (m,' +' -' + @KeepMonthsInDatabase + ', + GETDATE())' EXEC (@str) Adding ConnectionTimout = 0 did not help unfortunately.
What is the best way to re-index the table just maintained?
I 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
I would like to know the impacts (if any) of adding nonclustered index with included columns on large tables (these tables are populated by bulk insert from text files).
We have a table to 100M rows and up until now we were fine with an non clustered index a varchar(4000) because we never went above 900 bytes (yes it is a bad design).We have the need to support international character sets now so the column was updated to nvarchar(4000) and now we have data past the 900 byte limit.
The data is long, seems useless but is needed by the business and they need to be able to search "where bigcolumn like 'test%'". With an index, even with a huge amount of data, it was 'fast'. Now of course without an index it is unusable. The wildcard is always at the end of the search. I made a full text index on the column and basic queries such as: select * from ourtable where contains(bigcolumn, 'AReallyLongStringofTextHere') works fine unless there is a space in the data. We loose thousands of returned rows because of spaces in the data.
I have tried select * from ourtable where contains(bigcolumn, '"AReallyLongStringofTextHere that includes spaces"') but not all of the data is returned. I get 112 rows with the contains statement. The table scanning statement of "select * from ourtable where bigcolumn like 'AReallyLongStringofTextHere that includes spaces%' returns 1939 rows.I understand that a full text index is breaking the long string up since it contains spaces. Is there a way to retain the entire string as 1 index entry or is there a way to fix my query to return all of the rows?
please explain the differences btween this logical & phisicall operations that we can see therir graphical icons in execution plan tab in Management Studio
I have made a small mistake while restoring the DB I selected the 3rd option in the em
Leave the DB read-only and able to restore additional transactional logs
I have just realized that all I have is a complete back up to restore & no transaction logss...
I see the Db in a Read-only state & when I try to get it online It says Error 5063 : Db is a warm standby. A warm standby db is read-only Alter DB statement failed. sp_dboption command failed
I am using Full Text Index to index emails stored in BLOB column in a table. Index process parses stored emails, and, if there is one or more files attached to the email these documents get indexed too. In result when I'm querying the full text index for a word or phrase I am getting reference to the email containing the word of phrase if interest if the word was used in the email body OR if it was used in any document attached to the email.
How to distinguish in a Full Text query that the result came from an embedded document rather than from "main" document? Or if that's not possible how to disable indexing of embedded documents?
My goal is either to give a user an option if he or she wants to search emails (email bodies only) OR emails AND documents attached to them, or at least clearly indicate in the returned result the real source where the word or phrase has been found.
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.
My 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?
I know MMORPGs take tons of special servers, but what about a simple 2D minorly-multiplayer online game, say with 3-5 players- could that be run through an SQL database or is it still too slow?
Can someone share with me their experience or thougts on whether it is better to : 1) backup db to the disk first, then to the tape OR 2) use online backup which backup the database on realtime basis to the tape.
Can anyone tell me how I would go about making my SQL server accessable from the Internet, or know of any good tutorials to get me started, I haven't had much luck looking on google.
I need to access an SQL database from one server on another server for a web application.
I have started to learn SQL, I need to practise those commands through online sql interpreter. Is there any web page available to do so? or where can i down load it for free?
