concept dbcc PAGE in category sql server
This is an excerpt from Manning's book SQL Server 2008 Administration in Action.
Table 12.1 shows the full set of DBCC commands by category. Note that there are a number of undocumented commands not found in this list, such as DBCC PAGE, which we’ll cover later in the chapter.
One of the DBCC commands that we haven’t spoken of yet is DBCC PAGE, an undocumented (and therefore unsupported) command. If a database page is accessible, DBCC PAGE can be used to inspect its contents. In certain corruption scenarios, this can be very useful in determining the extent of damage. Consider a case where a range of clustered index (data) pages are corrupted—for example, pages 98 through 118. By inspecting the pages either side of the corruption range, 97 and 119 in this case, we’ll get a much better idea of the extent of damage.
Figure 12.6 shows the output of the DBCC PAGE command. Before running the command, we turn on trace flag 3604 to enable the output to be displayed to screen.
Figure 12.6. Using the undocumented (and unsupported) DBCC PAGE command to inspect the contents of a database page
As figure 12.6 shows, DBCC PAGE[3] will return data from the page that we can use to determine the contents, and thus the potential data loss—an important factor in deciding on an appropriate recovery option.