For scripts, Ola Hallengren has wicked awesome things maintenance. Use maintenance plans for now, once you become a little comfortable with the process of doing maintenance, switch to using scripts, running scheduled SQL agent jobs. On the weekends, it's DBCC, rebuild indexes, update stats. Don't shrink anything. Sign up to join this community.
The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. Asked 11 years, 9 months ago. Active 2 years, 11 months ago. Viewed 10k times.
Oh and I'm open to any links which might be of help! Customers often incorrectly attribute this improvement to the index rebuild itself, taking it to be result of reduced fragmentation and increased page density.
In reality, the same benefit can often be achieved at much cheaper resource cost by updating statistics instead of rebuilding indexes. Resource cost of updating statistics is minor compared to index rebuild, and the operation often completes in minutes instead of hours that may be required for index rebuilds.
Customers should perform it only when there is a demonstrated need, and taking into account the following points. This lets query workloads access tables while indexes are being rebuilt. Additionally, making the operation resumable lets you avoid restarting it from the beginning if it gets interrupted by a planned or unplanned database failover. Using resumable index operations is particularly important when indexes are large. Offline index operations typically complete faster than online operations.
They should be used when tables will not be accessed by queries during the operation, for example after loading data into staging tables as part of a sequential ETL process. Rowstore indexes with more than extents are rebuilt in two separate phases: logical and physical.
In the logical phase, the existing allocation units used by the index are marked for deallocation, the data rows are copied and sorted, then moved to new allocation units created to store the rebuilt index. In the physical phase, the allocation units previously marked for deallocation are physically dropped in short transactions that happen in the background, and do not require many locks. For more information about allocation units, see Pages and Extents Architecture Guide.
Even though the filegroup might have free space available, the user can still encounter error Could not allocate space for object ' ' in database ' ' because the ' ' filegroup is full. Create disk space by deleting unneeded files, dropping objects in the filegroup, adding additional files to the filegroup, or setting autogrowth on for existing files in the filegroup during the reorganize operation if a data file is out of space.
Up to SQL Server The Database Engine has to acquire an exclusive lock on the table or partition while the rebuild occurs. Creating and rebuilding nonaligned indexes on a table with more than 1, partitions is possible, but is not supported.
Doing so may cause degraded performance or excessive memory consumption during these operations. Microsoft recommends using only aligned indexes when the number of partitions exceeds 1, The following example determines the average fragmentation and page density for all rowstore indexes in the current database. This requires scanning all index pages, and may take a long time.
For more information, see sys. The following example determines the average fragmentation for all columnstore indexes with compressed row groups in the current database. Employee table in the AdventureWorks database. The following example reorganizes all indexes on the HumanResources. The following example rebuilds a single index on the Employee table in the AdventureWorks database. The following example rebuilds all indexes associated with the table in the AdventureWorks database using the ALL keyword.
Three options are specified. Skip to main content. This browser is no longer supported. Download Microsoft Edge More info. Contents Exit focus mode. Is this page helpful? Please rate your experience Yes No. Any additional feedback? The step failed. But if I do it on the table MyTab1 individually, it is fine. I removed MyTab1 from the list for rebuild, the I will get another error on another table with different error message.
When you're setting up your maintenance plan, you need to make sure you uncheck the box, in the rebuild indexes subplan, entitled:. Answering your question, Index Rebuild drops the existing Index and Recreates it, so there is no need to use reorganize that only works on the leaf nodes of the index. Online rebuilds are online available on the Enterprise version of SQL Server and your version probably isn't, so just set the operation not to be run "Online" on you Wizard.
Quick explanation: An online Rebuild, rebuilds the indexes on the tempDB making it available to the queries while it is being rebuilt. It is used when the operation takes a lot of time and you cant afford to leave the index "unused". My problem was because I had an offline database, which I was expecting to drop in the near future. After the database is dropped, the problem is went away. Stack Overflow for Teams — Collaborate and share knowledge with a private group.
Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Asked 9 years, 9 months ago. Active 7 years, 2 months ago. Considering Grant Fritchey's recommendations on setting the Threshold of Parallelism, I wonder how many other heavy-lifting tasks share that same "Sweet Spot'. He didn't forget about being able to rebuild indexes online. This is really helpful, but I think you are forgetting the rebuild index online, I know this could be helpful.
Thanks for the article. I'm curious of how you created the data, table and charts. Interesting that people are concerned about clearing the plan cache when the procedure in question is rebuild indexes and recompute statistics.
Both of those operations will force procedure re-compiles anyway and rightfully so. Another thing to think about is that using parallelism you will end up with indexes that are not fully defragmented, because they are being created in parallel threads. You really need to test and verify what is the most important part for you. Unless the SQL Server has a planned server reboot around the same time which will clear the cache as well Darek great idea on using sys.
Also an alternative solution is to use resource governor to manage parallelism. Hi Wilfred thanks for sharing your link with everyone, true for cases of non maintenance during normal database operation on MAXDOP usage, unfortunately it is outside scope of this article.
SQL Server automatically will use them. Example if your database has max degree of parallelism value of 1. Then Index maintenance will use "1" If it's "4" then it will use "4" If it's "8" then it will use "8". Maybe someone knows that. How to check how many parallel threads were used to create an index? Using explain plan doesn't show the information. You should NOT play with Maxdop at instance level just to improve your index rebuild. Depending of the type of your database, the setting of Maxdop has a huge impact on your performance.
Good and interesting article Norman. I shared with our DBA group. I see you are doing well. Another way of speeding up maintenance procedures is through use of the Service Broker; I have found it useful for update-stats runs. I like the article, straightforward and useful.
I also appreciate the comments, especially from alzdba regarding the procedure cache clearing. A great illustration of some many things in the SQL Server world that are like the ads for new cars: "Your mileage may vary". I wouldn't play around with Max Degree Of Parallelism at instance level because of 1 simple reason:.
Note Procedure cache will not be cleared if the actual value does not change or if the new value for the max server memory server option is set to 0. I forgot to tell you this.
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