The Totally Unauthorized List
of Sybase DBCC Commands

dbcc allocdump ( dbid, page )

Displays all extents on an allocation page.

Parameters
dbid	database ID
page	allocation page number

dbcc allocmap ( dbid, one_all, allocpg, bit_stat )

Display or modify status of allocation bitmaps used to detect full allocation pages.

Parameters
Param	Description	Valid Values
dbid	database ID
one_all	bitmap(s) to check/modify	0	entire allocation map
		1	single allocation map
allocpg	allocation page, if one_all = 1
bit_stat	status of the bits	0	check the status
		1	set the bit(s)
		2	clear the bit(s)

dbcc bhash ( print, bucket_limit )

Check integrity of and optionally print the buffer hash table.

Parameters
Param	Description	Valid Values
print	print option	print_bufs	display all buffers (default)
		no_print	display only buffers with problems
bucket_limit	number of buffers allowed in a bucket.	default = 0

dbcc bufcount ( n_chains )

Print up to 10 longest buffer chains and average chain length.

Parameters
Param	Description	Valid Values
n_chains	the number of chains to print	1-10

dbcc buffer ( [ dbid ][, objid ][, nbufs ], printopt, buftype )

Prints buffer headers and pages from the buffer cache.

Parameters
Param	Description	Valid Values
dbid	(optional) database name or database ID	0 will show data for all databases.
objid	(optional) object ID	0 will show data for all objects.
nbufs	(optional) number of buffers to examine.	If positive, the nbufs buffers which meet the other criteria (dbid, objid) are printed in MRU to LRU order. If negative, the last nbufs buffers which meet the criteria are printed in LRU to MRU order. If 0, all buffers will be printed in MRU to LRU order.
printopt	print option	0	print out only the buffer header and page header (default)
		1	print out each row separately and the offset table
		2	print out each row as a whole and the offset table
buftype	buffer type to print	Can be numeric or a symbolic character string. See table below for possible strings and their hexadecimal equivalents

Buffer Types
Param	Hex	Description
BUF_DIRTY	1	Buffer in cache differs from disk image.
BUF_IO	2	Buffer is being read or written.
BUF_PINNED	4	The log must be written before this buffer is.
BUF_KEPT	8	Some process is using this buffer.
BUF_RLOCK	10	The buffer is resource locked.
BUF_TRIP	20	The buffer ages out of cache more slowly.
BUF_NEW	40	Buffer contains a new page and has never been written.
BUF_RWAIT	80	The process is waiting for rlock.
BUF_IOERR	100	There was an error writing tis buffer.
BUF_SPECIAL	200	If this buffer is written, update relevant descriptors.
BUF_WQUEUE	400	This buffer is queued for an out-of-sequence database dump.
BUF_NOTHASHED	800	This buffer is not hashed.
BUF_HASHED	1000	This buffer is hashed.
BUF_DIAG	2000	This is a special buffer used for diagnostics only.
BUF_FILTHY	4000	The buffer was dirtied while in I/O (log only).
BUF_NORELEASE	8000	This is used for coordinating releases of rlocks on allocation pages.

dbcc bytes ( startaddress, length )

Dump out bytes from specific address.

Parameters
Param	Description
startaddress	starting address to dump
length	number of bytes to dump

dbcc cacheremove ( dbname, objectname )

Removes object from cache.

Parameters
Param	Description
dbname	database name
objname	object name

dbcc capture_tds (spid)

Captures Tabular Data Stream into a file called $SYBASE/install/TDSDUMP. File contains full stream, including passwords -- chmod the file to protect this information.

dbcc checkalloc [( dbname [, option ] )]

Check data and index pages against corresponding extent structures (earlier newalloc).

Parameters
Param	Description	Valid Values
dbname	(optional) database name
option	(optional) fix option	fix	report and fix descrepancies
		nofix	report decrepancies only (default)

dbcc checkcatalog [( dbname)]

Check consistency of system catalogs tables for database named.

Parameters
Param	Description
dbname	(optional) database name; default is current db

dbcc checkdb [( dbname [, skip_ncindex ] )]

Check consistency of data and index pages.

Parameters
Param	Description
dbname	(optional) database name; default is current db
skip_ncindex	(optional) skip check on non clustered indexes for the database

dbcc checktable ( tabid [, skip_ncindex ] )

Check consistency of data and index pages.

Parameters
Param	Description
tabid	table name or table ID
skip_ncindex	(optional) skip check on non clustered indexes for the table.

dbcc chgdbname ( dbname, newname )

Changes database name in DBINFO only.

Parameters
Param	Description
dbname	existing database name
newname	new database name

dbcc chgobjname ( objname, newname )

Changes object name in cache only.

Parameters
Param	Description
objname	existing object name
newname	new object name

dbcc cursorinfo ( cursor_level, cursor_name )

Displays cursor information.

Parameters
Param	Description
cursor_level	level number; -1 to get cursor info for all nesting levels
cursor_name	name of the cursor

dbcc dbinfo [( dbname )]

Print DBINFO structure for specified database.

Parameters
Param	Description
dbname	(optional) database name

dbcc dbrecover ( dbname )

This will have recovery run on a suspect database without rebooting the server.

Parameters
Param	Description
dbname	database name

dbcc dbrepair ( db, option [, table][, index] )

Repair system tables.

Parameters
Param	Description	Valid Values
db	database ID or database name
option	repair option	dropdb	drop the specified database
		findstranded	display stranded objects
		fixindex	rebuild the specified index; used on system catalogs only
		fixsysindex	correct pfreeoff value for sysindexes
		newthreshold	rebuild the database threshold table
		remap	update the in-core image of the database usage map table
		repairindex	repair index for user tables
table	(optional) table name
index	(optional) index ID

dbcc dbtable ( dbid )

Print out the contents of the DBTABLE structure.

Parameters
Param	Description
dbid	database ID

dbcc delbuff ( dbid, page, dirty_flush, kept_flag, rlock_flag )

Remove buffer from cache, optionally flush to disk.

Parameters
Param	Description
dbid	database ID
page	the logical page number of the page to be removed
dirty_flush	if 1, then flush the page to disk if DIRTY
kept_flag	if 1, then do not unkeep buffer if KEPT
rlock_flag	if 1, then do not remove RESOURCE LOCK

dbcc delete_row ( dbid, page, delete_by_row, rownum )

Delete an index or data row by either a row number or an offset on a page.

Parameters
Param	Description	Valid Values
dbid	database ID
page	the logical page number
delete_by_row	delete location; by row or by offset	1	next parameter is interpreted as row number
		0	next parameter is interpreted as offset on the page
rownum	either a row number or offset

dbcc des [( [ dbid ][, objid ] )]

Prints the contents of the specified DES (descriptor).

Parameters
Param	Description
dbid	(optional) database ID
objid	(optional) object ID

dbcc descount ( n_chains )

Print up to 10 longest DES chains. P>

Parameters
Param	Description
n_chains	the number of chains to print, up to 10.

dbcc desdiag ( dbid, option )

Produce DES diagnostic reports.

Parameters
Param	Description	Valid Values
dbid	database ID
option	diagnostic to run	-4	Display Hash Table Graph
		-3	Display Diagnostic Maps
		-2	Run all the tests (1-4)
		-1	Return to caller - Exit
		0	Redisplay this menu
		1	Check Free Des Chain
		2	Check Dbtable DES chain
		3	Check Des Kept/Unkept chain
		4	Check Des Name/Id hash table
		5	Display 'lost' descriptors
		6	Run tests (1-4), kepanic on errors

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