TAILIEUCHUNG - Brad’s Sure Guide to SQL Server Maintenance Plans- P22

Brad’s Sure Guide to SQL Server Maintenance Plans- P22: SQL Server has a reputation as being a simple database application to install, configure, and maintain. This is a little misleading. SQL Server is a powerful relational database that can handle the needs of the largest organizations and, as such, its proper maintenance almost certainly requires the attention of an experienced DBA. | Chapter 7 Rebuild Index Task Once the header information is displayed note that the command executes for each index in the database. 1 have abbreviated the report to only show two indexes being rebuilt as there were a lot more that were actually rebuilt in the full report. When and How Often to Rebuild Indexes The performance of your indexes and therefore your database queries will degrade as you indexes become fragmented. The Rebuild Index task does a very good job of rebuilding indexes to remove logical fragmentation and empty space and updating statistics. As such it is very important that you schedule this task to run regularly. On the other hand the Rebuild Index task is resource intensive. 1n addition as an index is being rebuilt locks will be placed on it preventing anyone from accessing it while the rebuilding occurs. Any queries trying to access this index in order to return the required results will be temporarily blocked until the rebuild is complete. As such the Rebuild Index task is considered an offline activity to be run when as few people as possible are accessing a database. 1n general this means during a scheduled maintenance window. 1t is quite difficult to offer general advice with regard to when and how often to rebuild indexes using the Maintenance Plan Wizard as it is so dependent on the nature of the data the indexes and the queries that use them. However take a look at my general advice with regard to index rebuilding and then we ll consider the advice in a little more detail over the coming sections. Nightly if required. 1f your indexes fragment rapidly and you have a nightly maintenance window that allows you to run the Rebuild Index task along with all the other maintenance tasks then do so. 1ndex fragmentation will degrade the performance of your indexes. Assuming that you have a maintenance window rebuilding every night can t do any harm and can very well boost the performance of your server. Weekly at minimum. 1f you can t perform .

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