We can use the undocumented DBCC PAGE command to view the page header, data rows, and row offset table for any data page in a database. You have to turn on traceflag 3604 before running this command. You can also use this command when you find the IO bottleneck and query is waiting Page Latches.
Permission: System Admin rights
Syntax
dbcc page ( {'dbname' | dbid}, file number, page number [, print opt={0|1|2|3} ])
You can pass the below print option parameter as per the requirement
- 0 - print just the page header
- 1 - page header plus per-row hex dumps and a dump of the page slot array (unless it’s a page that doesn't have one, like allocation bitmaps)
- 2 - page header plus whole page hex dump
- 3 - page header plus detailed per-row interpretation
Trace Flag – 3604 Trace flag 3604 is the most commonly used trace flag. It sends the output of a trace to the client. For example, before you can run DBCC PAGE, which views data page information, you must run this trace flag.
DBCC traceon(3604)
DBCC PAGE ( {dbid | dbname}, filenum, pagenum [, printopt] [, cache] )
The output from DBCC PAGE is divided into four main sections: Buffer, Page Header, Data, and Offset Table (really the Offset Array).
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