一段简单的 T-SQL 脚本示例如下: DECLARE@FragPercentASINT;DECLARE@IndexNameASNVARCHAR(256);DECLARE@TableNameASNVARCHAR(256);-- 游标定义,用于遍历所有索引DECLAREindex_cursorCURSORFORSELECTOBJECT_NAME(i.object_id),i.name,ps.avg_fragmentation_in_percentFROMsys.dm_db_index_physical_stats(DB_ID(),NULL,...
a.avg_fragment_size_in_pagesASPagesPerFrag, a.page_countASNumPages FROMsys.dm_db_index_physical_stats(DB_ID('DB Name'), NULL,NULL,NULL,'DETAILED') ASa JOINsys.indexesASb ONa.object_id=b.object_id ANDa.index_id=b.index_id WHEREavg_fragmentation_in_percent>0 ORDERBYObjectName,PercentFr...
How to check index fragmentation in SQL Server? SQL Server index fragmentation definition SQL Server index fragmentation occurs when the data pages in indexes are logically disordered, loosely filled, or overfilled. Locating and accessing physically non-contiguous data pages in the disk drive requires...
However, since database fragmentation is a major cause of poor performance I thought a discussion of how to minimize and deal with database fragmentation in SQL Server might be generally useful. Essentially, three types of fragmentation affect SQL Server: · File (disk) fragmentation. SQL Server...
SELECT object_id, index_id, avg_fragmentation_in_percent, page_count FROM sys.dm_db_index_physical_stats(DB_ID('your_db_name'), OBJECT_ID('your_one_table'), NULL, NULL, NULL); http://blogs.msdn.com/b/jorgepc/archive/2007/12/09/how-to-check-fragmentation-on-sql-server-2005.aspx...
In SQL Server 2000 and 7.0, DBCC SHOWCONTIG returns information about four types of fragmentation: internal fragmentation and three types of external fragmentation. But the values reported for two of these fragmentation types are meaningless when a table or index spans multiple files. In SQL Server...
In SQL Server, heaps are rightly treated with suspicion. Although there are rare cases where they perform well, they are likely to be the cause of poor performance. If a table is likely to have a large number of changes, then it can become fragmented due
Brent gave us a quick tutorial on the way SQL Server stores data in 8 KB “pages.” In a new or rebuilt index, the pages are all full and stored in order. But, as more data gets added, pages become split: not all pages are full and they occur out of order. This is the vital...
Understand that fragmentation(in SQL Server) is not introduction of free space or some kind of space between rows present in index. This is other myth which needs attention. Fragmentation is just mismatch between Logical ordering of Index keys and physical ordering of data at leaf level of ...
Connect to the managed cloud databases Azure SQL Database and Amazon Relational Database Service (RDS) for SQL Server. Install and run on virtual machines hosted in the cloud, such as Windows on Azure Virtual Machine (VM) and Windows on Amazon Elastic Compute Cloud (EC2)....