Wednesday, November 21, 2012

Pages and Extents in SQL Server

In SQL server data stored on page. Disk I/O operations are performed at the page level. A single page is consist of 8KB (8192 Bytes) and Eight physical contiguous pages are one Extents.

One Data Page (8KB) = 8192 Bytes

Page Header       =   96 Bytes
Data Rows         = 8060 Bytes
Row Offset Array  =   36 Bytes

Total Bytes per page is 8192 Bytes




If you want to read more about page and extents please check out this below Microsoft links
http://msdn.microsoft.com/en-us/library/ms190969(v=sql.105).aspx
Source : Microsoft