APPENDIX G
Dynamic Performance Tables

Dynamic performance tables are tables in which Oracle stores
system statistics. Part V of this book describes how the DBA can
access these tables to get information on system activity that may be
helpful in tuning the database and other aspects of the system.
When your database is first created, only SYS has access to the V$
tables. To allow other users to run products that require the V$
tables, such as SQL*DBA Monitor options and the Oracle
Performance Pack products, you must run the script UTLMONTR.sql
which is located in the $Oracle_HOME/rdbms/admin on UNIX
systems.

WARNING: The V$ tables are prone to frequent change.
If you would like a full listing of all the V$tables, you can
access the V$FIXED_VIEW_DEFINITION view. The table
layouts displayed are from Oracle7.3.2. We have made every
attempt to make the table descriptions as accurate and up to
date as possible, and we will continue to review the layouts
periodically.

Version 7 Dynamic Performance Tables:

V$ACCESS: Describes the owners of objects. You can join this
table to the V$SESSION table using the SID column to obtain
the tables a particular user is using.

SID --  VARCHAR2

Session number that is accessing an object. This column
can be joined to V$SESSION to access the username and
other session information

OWNER -- VARCHAR2

Owner of the object

OBJECT -- VARCHAR2

Name of the object

OB_TYP -- VARCHAR2

Type identifier for the object

V$ARCHIVE: Information on archive logs for each thread in the database
system. (Each row provides information for one thread.)

GROUP# -- NUMBER

Log file group number

THREAD# --  NUMBER

Log file thread number

SEQUENCE# -- NUMBER

Log file sequence number

CURRENT -- VARCHAR2

Archive log currently in use

FIRST_CHANGE# -- NUMBER

First SCN stored in the current log

V$BACKUP: Backup status of all online data files

FILE# -- NUMBER

File identifier

STATUS -- VARCHAR2

File status: NOT ACTIVE, ACTIVE (backup in progress),
OFFLINE NORMAL, or description of an error

CHANGE#-- NUMBER

System change number when backup started

TIME -- VARCHAR2

Time the backup started

V$ACTIVE_INSTANCES: Maps name to instance numbers for all instances that have a
database currently mounted

INST_NUMBER-- NUMBER

Instance number

INST_NAME-- VARCHAR2(60)

Instance name

V$BGPROCESS: Describes the background processes, for example, DBWR,
SMON, PMON, ARCH

PADDR -- RAW(4)

Address of the process state object

NAME -- VARCHAR2

Name of this background process

DESCRIPTION: VARCHAR2

Description of the background process

ERROR -- NUMBER

Error encountered

V$BH: This is a parallel server view. This view gives the status and
number of pings for every buffer in the SGA. It can also be used
to check the contents of the buffer cache for non-parallel-server
environments. Use the statement SELECT status, COUNT(*)
FROM v$bh GROUP BY status

FILE# -- NUMBER

Datafile identifier number (to find filename, query DBA_
DATA_FILES or V$DBFILES)

BLOCK -- NUMBER

Block number

STATUS -- VARCHAR2(1)

FREE = not currently in use XCUR = exclusive, SCUR =
shared current, CR = consistent read, READ = being read
from disk, MREC = in media recovery mode, IREC = in
instance recovery mode

XNC -- NUMBER

Number of PCM lock conversions due to contention with
another instance. See Chapter 12, Tuning Parallel Server for
more information on this parameter.

LOCK_ELEMENT_ADDR -- RAW(4)

Address of the lock element that contains the PCM lock that
is covering the buffer. If more than one buffer has the same
address, these buffers are covered by the same PCM lock.

DIRTY -- VARCAHR2(1)

Y= modified block

TEMP -- VARCHAR2(1)

Y = temporary block

PING -- VARCHAR2(1)

Y = block pinged

STALE -- VARCHAR2(1)

Y = block is stale

DIRECT -- VARCHAR2(1)

Y = direct block

NEW -- VARCHAR2(1)

Y = new block

For more information, see the Oracle7 Parallel Server Concepts
and Administration.	

V$CACHE: This is a parallel server view. This view contains information
from the block header of each block in the SGA of the current
instance as related to particular database objects.

FILE# -- NUMBER

Data file identifier number (to find filename, query DBA_
DATA_FILES or V$DBFILES)

BLOCK# -- NUMBER

Block number

STATUS -- VARCHAR2(1)

Status of block:

FREE = not currently in use
XCUR = exclusive
SCUR = shared current
CR = consistent read
READ = being read from disk
MREC = in media recovery mode
IREC = in instance recovery mode

XNC -- NUMBER

Number of PCM lock conversions due to contention with
another instance

NAME -- VARCHAR2(30)

Name of the database object containing the block

KIND -- VARCHAR2(12)

Type of database object:

TABLE
CLUSTER
INDEX
UNDO = rollback segment

OWNER# -- NUMBER

Owner number

LOCK_ELEMENT_ADDR -- RAW(4)

Address of the lock element that contains the PCM lock that
is covering the buffer.  If more than one buffer has the
same address, then these buffers are covered by the same
PCM lock.

For more information, see the Oracle7 Parallel Server Concepts
and Administration.

V$CACHE_LOCK: This is a parallel server view. See Chapter 12, Tuning Parallel
Server, for more information on its usage.

FILE# -- NUMBER

Data file identifier number (to find filename, query DBA_
DATA_FILES or V$DBFILES)

BLOCK# -- NUMBER

Block number

STATUS -- VARCHAR2(4)

Status of block:

FREE = not currently in use
XCUR = exclusive
SCUR = shared current
CR = consistent read
READ = being read from disk
MREC = in media recovery mode
IREC = in instance recovery mode

XNC -- NUMBER

Number of parallel cache management (PCM) lock
conversions due to contention with another instance

NAME -- VARCHAR2(30)

Name of the database object containing the block

KIND -- VARCHAR2(12)

Type of database object:

TABLE
CLUSTER
INDEX
UNDO = rollback segment

OWNER# -- NUMBER

Owner number

LOCK_ELEMENT_ADDR -- RAW(4)

Address of the lock element that contains the PCM lock that
is covering the buffer.  If more than one buffer has the
same address, then these buffers are covered by the same
PCM lock.

INDX -- NUMBER

Platform-specific lock manager identifier

CLASS -- NUMBER

Platform-specific lock manager identifier

V$CACHE_LOCK is similar to V$CACHE, except for the platform
specific lock manager identifiers.  This information may be
useful if the platform specific lock manager provides tools for
monitoring the PCM lock operations that are occurring.  For
example, first query to find the lock element address using
INDX and CLASS, then query V$BH to find the buffers that are
covered by the lock,

For more information, see Oracle7 Parallel Server Concepts and
Administration.

V$CIRCUIT: This view  contains information about virtual circuits, which are
user connections to the database through dispatchers and servers.

CIRCUIT -- RAW(4)

Circuit address

DISPATCHER -- RAW(4)

Current dispatcher process address

SERVER -- RAW(4)

Current server process address

WAITER -- RAW(4)

Address of server process that is waiting for the (currently
busy) circuit to become available

SADDR -- RAW(4)

Address of session bound to the circuit

STATUS -- VARCHAR2

Status of the circuit: BREAK (currently interrupted), EOF
(about to be removed), OUTBOUND (an outward link to a
remote database), NORMAL (normal circuit into the local
database)

QUEUE -- VARCHAR2

Queue the circuit is currently on: COMMON (on the
common queue, waiting to be picked up by a server
process), DISPATCHER (waiting for the dispatcher),
SERVER (currently being served), OUTBOUND (waiting to
establish an outbound connection, NONE (idle circuit)

MESSAGE0 -- NUMBER

Size in bytes of the messages in the first message buffer

MESSAGE1 -- NUMBER

Size in bytes of the messages in the second message buffer

MESSAGES -- NUMBER

Total number of messages that have gone through this
circuit

BYTES -- NUMBER

Total number of bytes that have gone through this circuit

BREAKS -- NUMBER

Total number of breaks (interruptions) for this circuit

V$COMPATIBILITY: This view shows features in use by the database instance that
may prevent downgrading to a previous release.  This is the
dynamic (SGA) version of this information and may include
temporary incompatibilities (like UNDO segments) that will not
exist after the database is shut down cleanly.

TYPE_ID -- VARCHAR2(8)

Internal feature identifier

RELEASE -- VARCHAR2(60)

Release in which that feature appeared

DESCRIPTION -- VARCHAR2(64)

Description of the feature

V$COMPATSEG: This view lists the permanent features in use by the database
that will prevent moving back to an earlier release.

TYPE_ID -- VARCHAR2(8)

Internal feature identifier

RELEASE -- VARCHAR2(60)

Release in which that feature appeared.  The software must
be able to interpret data formats added in that release.

UPDATED -- VARCHAR2(60)

Release that first used the feature

V$CONTROLFILE: This view lists the names of the control files.

STATUS -- VARCHAR2(7)

INVALID if the name cannot be determined, which should
not occur

NULL if the name can be determined

NAME -- VARCHAR2(257)

Name of the control file

V$DATABASE: Database information from the control file

NAME -- VARCHAR2

Name of the database

CREATED -- VARCHAR2

Creation data

LOG_MODE -- VARCHAR2

Archive log mode: NOARCHIVELOG or ARCHIVELOG

CHECKPOINT_CHANGE# -- NUMBER

Last SCN checkpointed

ARCHIVE_CHANGE# -- NUMBER

Last SCN archived

V$DATAFILE: Data file information from the control file. Join this table to the
V$FILESTAT table to obtain a collection of I/O statistics for each
of your data files.

FILE# -- NUMBER

File identification number

STATUS -- VARCHAR2

Type of file (system or user) and its status

Values: OFFLINE, SYSOFF, ONLINE, SYSTEM, RECOVER

ENABLED -- VARCHAR2(10)

DISABLED means no SQL access allowed, READ ONLY no
SQL updates allowed, READ WRITE full access allowed and
UNKNOWN will occur if the control file is corrupted.

CHECKPOINT_CHANGE# -- NUMBER

SCN at last checkpoint

BYTES -- NUMBER

Size in bytes

CREATE_BYTES -- NUMBER

Size when created in bytes

NAME -- VARCHAR2

Name of the file

V$DBFILE: This view lists all datafiles making up the database.  This
view is retained for historical compatibility.  Use of V$DATAFILE
is recommended instead.

FILE# -- NUMBER

File identifier

NAME -- VARCHAR2

Name of file

V$DBLINK: This view describes all open database links (links with IN_
TRANSACTION = YES).  These database links must be
committed or rolled back before being closed.

DB_LINK -- VARCHAR2(128)

Name of the database link

OWNER_ID -- NUMBER

Owner of the database link UID

LOGGED_ON -- VARCHAR2(3)

Whether the database link is currently logged on

HETEROGENEOUS -- VARCHAR2(3)

Whether the database link is heterogeneous

PROTOCOL -- VARCHAR2(6)

Communication protocol for the database link

OPEN_CURSORS -- NUMBER

Whether there are open cursors for the database link

IN_TRANSACTION -- VARCHAR2(3)

Whether the database link is currently in a transaction

UPDATE_SENT -- VARCHAR2(3)

Whether there has been an update on the database link

COMMIT_POINT_STRENGH -- NUMBER

Commit point strength of the transactions on the database link

V$DB_OBJECT_CACHE: Shows database objects that are cached
in the library cache.  Objects include tables,
indexes, clusters, synonym definitions, PL/SQL
procedures and packages, and triggers. The important
columns from the tuning perspective are the LOADS and
EXECUTIONS. If an object is being executed frequently and has
to be reloaded often, the reloading usually implies that your
SHARED_POOL_SIZE is set to small. You should also consider
pinning your objects in the library cache using the DBMS_
SHARED_POOL.keep procedure. If an object is pinned, the
column KEPT will have a value of `YES'.

OWNER -- VARCHAR2

Owner of the object

NAME -- VARCHAR2

Name of the object

DB_LINK -- VARCHAR2

Database link name, if any

NAMESPACE -- VARCHAR2

Library cache namespace of the object: TABLE/PROCEDURE BODY,
TRIGGER, INDEX, CLUSTER, OBJECT

TYPE -- VARCHAR2

Type of object: INDEX, TABLE, CLUSTER, VIEW, SET,
SYNONYM, SEQUENCE, PROCEDURE, FUNCTION,
PACKAGE, PACKAGE BODY, TRIGGER, CLASS, OBJECT,
USER, DBLINK

SHARABLE_MEM -- NUMBER

Amount of sharable memory in the shared pool consumed
by the object

LOADS -- NUMBER

Number of times the object has been loaded... This count
also increases when an object has been invalidated.

EXECUTIONS -- NUMBER

Total number of times this object has been executed

LOCKS -- NUMBER

Number of users currently locking this object

PINS -- NUMBER

Number of users currently pinning this object

KEPT -- VARCHAR2(3)

YES or NO, depending on whether this object has been
kept in the shared pool using DBMS_SHARED_POOL.KEEP
or not

V$DB_PIPES: This view shows the pipes that are currently in this database.

OWNERID -- NUMBER

Owner of the pipe if this is a private pipe; null otherwise

NAME -- VARCHAR2

Name of the pipe; for example, scott.pipe

TYPE -- VARCHAR2

PUBLIC or PRIVATE

SIZE -- NUMBER

The amount of memory the pipe uses

V$DISPATCHER: Information on the dispatcher processes.

NAME -- VARCHAR2

Name of the dispatcher process

NETWORK -- VARCHAR2

Network protocol supported by this dispatcher; for
example, TCP or DECNET

PADDR -- RAW(4)

Process address

STATUS -- VARCHAR2

Dispatcher status: WAIT (idle), SEND (sending a message),
RECEIVE (receiving a message), CONNECT (establishing a
connection), DISCONNECT (handling a disconnect
request), BREAK (handling a break), OUTBOUND
(establishing an outbound connection)

ACCEPT -- VARCHAR2

Whether this dispatcher is accepting new connections: YES, NO

MESSAGES -- NUMBER

Number of messages processed by this dispatcher

BYTES -- NUMBER

Size in bytes of messages processed by this dispatcher

BREAKS -- NUMBER

Number of breaks occurring in this connection

OWNED -- NUMBER

Number of circuits owned by this dispatcher

CREATED -- NUMBER

Number of circuits created by this dispatcher

IDLE -- NUMBER

Total idle time for this dispatcher, in hundredths of a
second

BUSY -- NUMBER

Total busy time for this dispatcher, in hundredths of a
second

LISTENER -- NUMBER

The most recent Oracle error number that the dispatcher
received from  the listener

V$ENABLEDPRIVS: Which privileges are enabled.

PRIV_NUMBER -- NUMBER

Numeric identifier of enabled privileges

V$EVENT_NAME: This view contains information about wait events.

EVENT# -- NUMBER

Number of the wait event

NAME -- VARCHAR2(64)

Name of the wait event

PARAMETER1 -- VARCHAR2(64)

Description of the first parameter for the wait event

PARAMETER2 -- VARCHAR2(64)

Description of the second parameter for the wait event

PARAMETER3 -- VARCHAR2(64)

Description of the third parameter for the wait event

V$FALSE_PING: This is a parallel server view. This view shows buffers that may
be getting false pings;  that is, buffers pinged more than 100
times that are protected by the same lock as another buffer that
pinged more than 100 times.  Buffers identified as getting false
pings can be remapped in GC_FILES_TO_LOCKS to reduce lock
collisions.

FILE# -- NUMBER

Data file identifier number (to find filename, query DBA_
DATA_FILES or V$DBFILES)

BLOCK# -- NUMBER

Block number

STATUS -- VARCHAR2(1)

Status of block;

FREE = not currently in use
XCUR = exclusive
SCUR = shared current
CR = consistent read
READ = being read from disk
MREC = in media recovery mode
IREC = in instance recovery mode

XNC -- NUMBER

Number of PCM lock conversions due to contention with
another instance

NAME -- VARCHAR2(30)

Name of the database object containing the block

KIND -- VARCHAR2(12)

Type of database object:

TABLE, CLUSTER, INDEX, or UNDO = rollback segment

OWNER# -- NUMBER

Owner number

LOCK_ELEMENT_ADDR -- RAW(4)

Address of the lock element that contains the PCM lock that
is covering the buffer.  If more than one buffer has the
same address, then these buffers are covered by the same
PCM lock.

For more information, see Oracle7 Parallel Server Concepts and
Administration.

V$FILESTAT: Information about file read/write statistics. Use the FILE#
column to join to the V$DATAFILE table, to obtain the file name.

FILE# -- NUMBER

Number of the file. Can be used to join to V$DATAFILE.

PHYRDS -- NUMBER

Number of physical reads done

PHYWRTS -- NUMBER

Number of physical writes done

PHYBLKRD -- NUMBER

Number of physical blocks read

PHYBLKWRT -- NUMBER

Number of physical blocks written

READTIM -- NUMBER

Time spent doing reads if the parameter TIMED_
STATISTICS is TRUE; 0 if FALSE

WRITETIM -- NUMBER

Time spent doing writes if the parameter TIMED_
STATISTICS is TRUE; 0 if FALSE

V$FIXED_TABLE: Shows all fixed tables, views, and derived
tables in the database

NAME -- VARCHAR2

Name of the object

OBJECT_ID -- NUMBER

Identifier of the fixed object

TYPE -- VARCHAR2

Object type: TABLE, VIEW

TABLE_NUM -- NUMBER

Number that identifies the dynamic performance table if it
is of type TABLE

V$FIXED_VIEW_DEFINITION: This view  contains the definitions
of all the fixed views (views beginning with V$).
Use this table with caution.  Oracle tries to
keep the behavior of fixed views the same from release to
release, but the definitions of the fixed views can change
without notice.  Use these definitions to optimize your queries
by using indexed columns of the dynamic performance tables.

VIEW_NAME -- VARCHAR2(30)

Name of the dynamic performance table that is indexed

VIEW_DEFINITION -- VARCHAR2(2000) T

Definition of the view

V$INDEXED _FIXED_COLUMN: This view shows the columns in
dynamic performance tables (X$ tables) that are indexed.
The X$ tables can change without notice.  Use this view
only to write queries against fixed views (V$ views) more
efficiently.

TABLE_NAME -- VARCHAR2(30)

Name of the dynamic performance table that is indexed

INDEX_NUMBER -- NUMBER

Number that distinguishes to which index a column
belongs

COLUMN_NAME -- VARCHAR2(30)

Name of the column that is being indexed

COLUMN_POSITION -- NUMBER

Position of the column in the index key. This is mostly
relevant for multicolumn indexes.

V$INSTANCE: State of the current instance.

KEY -- VARCHAR2

Name of state variable, from the table below

VALUE -- NUMBER

Value of state variable; may be RESTRICTED MODE -- 0 (False),
1 (True), SHUTDOWN PENDING -- 0 (False), 1 (True),
STARTUP TIME-JULIAN -- Start time and date in Julian format, or
STARTUP TIME-SECONDS -- Number of seconds since midnight on
the startup date

V$LATCH: Information about each type of latch. The view contains counts
for child latches and summary statistics for parent latches. The
different types of latch contention are documented in Chapter
11, Monitoring and Tuning an Existing Database. The higher
the ratio of GETMISSES to GETS and IMMEDIATE_MISSES to
IMMEDIATE_GETS, the worse your latch contention.

ADDR -- RAW(4)

Address of latch object

LATCH# -- NUMBER

Latch number

LEVEL# -- NUMBER

Latch level

NAME -- VARCHAR2(64)

Latch Name

GETS -- NUMBER

Number of times obtained with wait

MISSES -- NUMBER

Number of times obtained with wait but failed first try

SLEEPS -- NUMBER

Number of times slept when wanted wait

IMMEDIATE_GETS -- NUMBER

Number of times obtained with no wait

IMMEDIATE_MISSES -- NUMBER

Number of times failed to get with no wait

WAITERS_WOKEN -- NUMBER

Number of times that a waiter has woken

WAITS_HOLDING_ LATCH_NUMBER -- Number of waits while holding
a different latch

SPIN_GETS -- NUMBER

Gets that had to spin on more than once to obtain the latch

SLEEP1 -- NUMBER

Waits that slept 1 time

SLEEP2 -- NUMBER

Waits that slept 2 times

SLEEP3 -- NUMBER

Waits that slept 3 times

SLEEP4 -- NUMBER

Waits that slept 4 times

SLEEP5 -- NUMBER

Waits that slept 5 times

SLEEP6 -- NUMBER

Waits that slept 6 times

SLEEP7 -- NUMBER

Waits that slept 7 times

SLEEP8 -- NUMBER

Waits that slept 8 times

SLEEP9 -- NUMBER

Waits that slept 9 times

SLEEP10 -- NUMBER

Waits that slept 10 times

SLEEP11 -- NUMBER

Waits that slept 11 times

V$LATCHHOLDER: Information about the current latch holders

PID -- NUMBER

Identifier of process holding the latch

SID -- NUMBER

Identifier of the session that own the latch

LADDR -- RAW(4)

Latch address

NAME -- VARCHAR2

Name of the latch being held

V$LATCHNAME: This table was used to obtain the latch name in the V$LATCH
table. The latch name is now stored in the V$LATCH table,
making this table obsolete.

LATCH# -- NUMBER

Latch number

NAME -- VARCHAR2(64)

Latch name

V$LATCH_CHILDREN: This view  contains statistics about child latches.
This view includes all columns of V$LATCH plus the CHILD# column.
Note that child latches have the same parent if their LATCH#
columns match each other.

ADDR -- RAW(4)

Address of latch object

LATCH# -- NUMBER

Latch number for a parent latch

CHILD# -- NUMBER

Child number of a parent latch shown in LATCH#

LEVEL# -- NUMBER

Latch level

NAME -- VARCHAR2(64)

Latch name

GETS -- NUMBER

Number of times gotten wait

MISSES -- NUMBER

Number of times gotten wait but failed first try

SLEEPS -- NUMBER

Number of times slept when wanted wait

IMMEDIATE_GETS -- NUMBER

Number of times gotten without wait

IMMEDIATE_MISSES -- NUMBER

Number of time failed to get without wait

WAITERS_WOKEN -- NUMBER

How many times a waiter was woken

WAITS_HOLDING_LATCH -- NUMBER

Number of waits while holding a different latch

SPIN_GETS -- NUMBER

Gets that missed first try but succeeded on spin

SLEEPn -- NUMBER

Waits that slept n times

V$LATCH_MISSES: This view contains statistics about missed
attempts to acquire a latch.

PARENT_NAME -- VARCHAR2

Latch name of a parent latch

WHERE -- VARCHAR2

Location that attempted to acquire the latch

NWFAIL_COUNT -- NUMBER

Number of times that no-wait acquisition of the latch failed

SLEEP_COUNT -- NUMBER

Number of times that acquisition attempts caused sleeps

V$LATCH_PARENT: This view contains statistics about the parent
latch.  The columns of V$LATCH_PARENT are identical to those
in V$LATCH listed earlier.

V$LIBRARYCACHE: Statistics on library cache management. If you
enlarge your SHARED_POOL_SIZE and see a pronounced reduction in the
number of RELOADS, there is a high probability that your
performance will be improved.

NAMESPACE -- VARCHAR2

Library cache namespace: SQL AREA, TABLE/PROCEDURE,
BODY, TRIGGER, INDEX, CLUSTER, OBJECT, PIPE

GETHITS -- NUMBER

Number of times the handles are already allocated in the
cache. If the handle is not already allocated, it is a miss.
The handle is then allocated and inserted into the cache.

GETHITRATIO -- NUMBER

Number of GETHITS divided by GETS. Values close to 1
indicate that most of the handles the system has tried to get
are cached.

PINS -- NUMBER

Number of times the system issues pin requests for objects
in the cache to access them

PINHITS -- NUMBER

Number of times that objects the system is pinning and
accessing are already allocated and initialized in the cache.
Otherwise, it is a miss, and the system has to allocate it in
the cache and initialize it with data queried from the
database or generate the data.

PINHITRATIO -- NUMBER

Number of PINHITS divided by number of PINS. Values
close to 1 indicate that most of the objects the system has
tried to pin and access have been cached.

RELOADS -- NUMBER

Number of times that library objects have to be reinitialized
and reloaded with data because they have been aged out
or invalidated

INVALIDATIONS -- NUMBER

Number of times that no-persistent library objects (like
shared SQL areas) have been invalidated

DLM_LOCK_REQUESTS -- NUMBER

Number of GET lock instance  locks. DLM stands for the
distributed lock manager, which is used for parallel server.

DLM_PIN_REQUESTS -- NUMBER

Number of PIN distributed lock manager locks

DLM_PIN_RELEASES -- NUMBER

Number of releases on a pin by the distributed lock
manager

DLM_INVALIDATION_REQUESTS -- NUMBER

Number of distributed lock manager requests for
invalidation instance locks

DLM_INVALIDATIONS -- NUMBER

Number of invalidation pings received from other instances

V$LICENSE: Information about license limit.

SESSIONS_MAX -- NUMBER

Maximum number of concurrent user sessions allowed for
the instance

SESSIONS_WARNING --NUMBER

Warning limit for concurrent user sessions for the instance

SESSION_CURRENT -- NUMBER

Current number of concurrent user sessions

SESSION_HIGHWATER -- NUMBER

Highest number of concurrent user sessions since the
instance started

USERS_MAX -- NUMBER

Maximum number of named users allowed for the database

V$LOADCSTAT: SQL*Loader statistics compiled during the execution of
a direct load. These statistics apply to the whole load. Any select
against this table results in "no rows returned," since you cannot
load data and do a query at the same time.

READ -- NUMBER

Number of records read

REJECTED -- NUMBER

Number of records rejected

TDISCARD -- NUMBER

Total number of discards during the load

NDISCARD -- NUMBER

Number of discards from the current file

SAVEDATA -- NUMBER

Whether or not save data points are used

V$LOADTSTAT: SQL* Loader statistics compiled during the execution of a direct
load. These statistics apply to the current table. Any select
against this table results in "no rows returned," since you cannot
load data and do a query at the same time.

LOADED -- NUMBER

Number of records loaded

REJECTED -- NUMBER

Number of records rejected

FAILWHEN -- NUMBER

Number of records that failed to meet any WHEN clause

ALLNULL -- NUMBER

Number of records that were completed

LEFT2SKIP -- NUMBER

Number of records yet to skip during a continued load

The following locks are obtained by user applications. Any process
that is blocking others is likely to be holding one of these locks:
TM (DML enqueue lock), TX (Transaction enqueue lock), or UL
(User supplied lock).

The following system locks are held for extremely short periods of
time: BL (Buffer hash table instance lock), CF (Cross-instance
function invocation instance lock), CI (Control file schema
global enqueue lock), CU (Cursor bind lock), DF (Data file
instance lock), DM (Mount/startup db primary/secondary instance lock),
DR (Distributed recovery process lock), DX )Distributed
transaction entry lock), FS (File set lock), IN (Instance
number lock), IR (Instance recovery serialization global enqueue
lock), IS (Instance state lock), IV (Library cache invalidation
instance lock), JQ (Job queue lock), KK (Thread kick lock)
LA..LP (Library cache lock instance lock (A..P=namespace),
MM (Mount definition global enqueue lock) MR (Media recovery lock),
NA..NZ (Library cache pin instance lock (A..Z=namespace)),
PF (Password file lock), PI,PS (Parallel lock operations),
PR (Process startup lock), QA..QZ (Row cache instance lock
(A..Z=cache)), RT (Redo thread global enqueue lock),
SC (System commit number instance lock), SM (SMON Lock),
SN (Sequence number instance lock), SQ (Sequence number enqueue
lock), SS (Sort segment locks), ST (Space transaction enqueue
lock, SV (Sequence number value lock), TA (Generic enqueue
lock), TS (Temporary segment enqueue lock (ID2=0) or New
block allocation enqueue lock (ID2=1), TT (Temporary
table enqueue lock), UN (User name lock), US (Rollback
segment DDL lock), or WL (Being-written redo log instance lock).

V$LOCK: This view lists the locks currently held by the Oracle7 server
and outstanding requests for a lock or latch. The SID column in this
table can be used to find the user that is holding the lock. The
column ID1 has various meaning depending on the lock type,
but the most important use of the column is for a transaction
lock, when ID1 is the OBJECT_ID column in the ALL_OBJECTS
view.

ADDR -- RAW(4)

Address of lock state object

KADDR -- RAW(4)

Address of lock

SID -- NUMBER

Identifier for session holding or acquiring the lock

TYPE -- VARCHAR2(2)

Type of lock: MR (Media Recovery), RT (Redo Thread),
UN (User Name), TX (Transaction), TM (DML), UL (PL/SQL User Lock),
DX (Distributed Xaction), CF (Control File), IS (Instance State),
DS (File Set), IR (Instance Recovery), ST (Disk Space Transaction),
TS (Temp Segment), IV (Library Cache Invalidation), LS (Log
Start or Switch), RW (Row Wait), SQ (Sequence Number), TE (Extend
Table), TT (Temp Table).

ID1 -- NUMBER

Lock identifier #1 (depends on type)

ID2 -- NUMBER

Lock identifier #2 (depends on type)

LMODE -- NUMBER

Mode the lock is currently held in by the session:

0, None
1, Null
2, Row-S (SS)
3, Row-X (SX)
4, Share
5, S/Row-X (SSX)
6, Exclusive

REQUEST -- NUMBER

Mode of the lock requested by the process

0, None
1, Null
2, Row-S (SS)
3, Row-X (SX)
4, Share
5, S/Row-X (SSX)
6, Exclusive

CTIME -- NUMBER

Time since current mode was granted

BLOCK -- NUMBER

The lock is blocking another lock

V$LOCK_ACTIVITY: This is a Parallel Server view. V$LOCK_ACTIVITY shows the
DLM lock operation activity of the current instance.  Each row
corresponds to a type of lock operation.

FROM_VAL -- VARCHAR2(4)

PCM lock initial state: NULL, S, X, or SSX

TO_VAL -- VARCHAR2(4)

PCM lock initial state: NULL, S, X, or SSX

ACTION_VAL -- VARCHAR2(51)

Description of lock conversations

Lock buffers for read
Lock buffers for write
Make buffers CR (no write)
Upgrade read lock to write
Make buffers CR (write dirty buffers)
Downgrade write lock to read (write dirty buffers)
Write transaction table/undo blocks
Transaction table/undo blocks (write dirty buffers)
Make transaction table/undo blocks available share
Rearm transaction table write mechanism

COUNTER -- NUMBER

V$LOCK_ELEMENT: This is a Parallel Server view.

LOCK_ELEMENT_ADDR -- RAW(4)

Address of the lock element that contains the PCM lock that
is covering the buffer.  If more than one buffer has the
same address, then these buffers are covered by the same
PCM lock.

INDX -- NUMBER

Platform specific lock manager identifier

CLASS -- NUMBER

Platform specific lock manager identifier

MODE_HELD -- NUMBER

Platform dependent value for lock mode held; often:
3 = share, or 5 = exclusive

BLOCK_COUNT -- NUMBER

Number of blocks covered by PCM lock

RELEASING -- NUMBER

Nonzero if PCM lock is being downgraded

ACQUIRING -- NUMBER

Nonzero if PCM lock is being upgraded

INVALID -- NUMBER

Nonzero if PCK lock is invalid. (A lock may become invalid
after a system failure.)

V$LOCKED_OBJECT: This view lists all locks acquired by every
transaction on the system.

XIDUSN -- NUMBER

Undo segment number

XIDSLOT -- NUMBER

Slot number

XIDSQN -- NUMBER

Sequence number

OBJECT_ID -- NUMBER

Object ID being locked

SESSION_ID -- NUMBER

Session ID

Oracle_USERNAME -- VARCHAR2(30)

Oracle user name

OS_USER_NAME -- VARCHAR2(15)

OS user name

PROCESS -- VARCHAR2(9)

OS process ID

LOCKED_MODE -- NUMBER

Lock mode

V$LOCKS_WITH_COLLISIONS: This is a parallel server view.

LOCK_ELEMENT_ADDR -- RAW(4)

Address of the lock element that contains the PCM lock
covering the buffer.  If more than one buffer has the same
address, then these buffers are covered by the same PCM
lock.

V$LOG: Log file information from control file.

GROUP# -- NUMBER

Log group number

THREAD# -- NUMBER

Log thread number

SEQUENCE# -- NUMBER

Log sequence number

BYTES -- NUMBER

Size of the log in bytes

MEMBERS -- NUMBER

Number of members in the log group

ARCHIVED -- VARCHAR2

Archived status: TRUE, FALSE

STATUS -- VARCHAR2(16)

Can have the value:

UNUSED, which indicates that the log has never been
written to

CURRENT if the log is current redo log being written to

ACTIVE means that the redo log is not the current one
being written to but it is active and can be written to

CLEARING means that somebody has used the ALTER
DATABASE CLEAR LOGFILE command

CLEARING_CURRENT means that the log is currently being
cleared

INACTIVE means the redo log is no longer required for
instance recovery.

FIRST_CHANGE# -- NUMBER

Lowest SCN in the log

FIRST_TIME -- VARCHAR2

Time of first SCN in the log

V$LOGFILE: Information about redo log files

GROUP# -- NUMBER

Redo log group identifier number

STATUS -- VARCHAR2

Status of this log member: INVALID (file is inaccessible),
STALE (file's contents are incomplete), DELETED (file is no
longer used), or blank (file is in use)

MEMBER -- VARCHAR2

Redo log member name

V$LOGHIST: Log history information from the control file. This view is
retained for historical compatibility. Use of V$LOG_HISTORY is
recommended instead.

THREAD# -- NUMBER

Log thread number

SEQUENCE# -- NUMBER

Log sequence number

FIRST_CHANGE# -- NUMBER

Lowest SCN in the log

FIRST_TIME -- VARCHAR2

TIME OF FIRST SCN in the log

SWITCH_CHANGE# -- NUMBER

SCN at which the log switch occurred; one more than
highest SCN in the log

V$LOG_HISTORY: Archived log names for all logs in the log history.

THREAD# -- NUMBER

Thread number of the archived log

SEQUENCE# -- NUMBER

Sequence number of the archived log

TIME -- NUMBER

Time of first entry (lowest SCN) in the log

LOG_CHANGE# -- NUMBER

Lowest SCN in the log

HIGH_CHANGE# -- NUMBER

Highest SCN in the log

ARCHIVE_NAME -- VARCHAR2

Name of file when archived, using the naming convention
specified by the LOG_ARCHIVE_FORMAT initialization
parameter

V$MLS_PARAMETERS: This is a Trusted Oracle7 server view that
lists Trusted Oracle7 server-specific initialization parameters.

V$MTS: This view contains information for tuning the multithreaded
server.

MAXIMUM_CONNECTIONSi -- NUMBER

Maximum number of connections each dispatcher can
support.  This value is determined at startup time using
SQL*Net constants and other port-specific information.

SERVERS_STARTED -- NUMBER

Total number of multithreaded servers started since the
instance started (but not including those started during
startup)

SERVERS_TERMINATED -- NUMBER

Total number of multithreaded servers stopped by Oracle
since the instance started

SERVERS_HIGHWATER -- NUMBER

Highest number of servers running at one time since the
instance started.  If this value reaches the value set for the
MTS_MAX_SERVERS initialization parameter, consider
raising the value of MTS_MAX_SERVERS.

V$MYSTAT: This view contains statistics on the current session.

SID -- NUMBER

ID of the current session

STATISTIC# -- NUMBER

Number of the statistic

VALUE -- NUMBER

Value of the statistic

V$NLS_PARAMETERS: Current values of NLS parameter.

PARAMETER -- VARCHAR2

Parameter name: NLS_LANGUAGE, NLS_SORT, NLS_
TERRITORY, NLS_CHARACTERSET, NLS_CURRENCY, NLS_
ISO_CURRENCY, NLS_NUMERIC_CHARACTERS, NLS_
FORMAT, NLS_DATA_LANGUAGE

VALUE -- VARCHAR2

NLS parameter value

V$NLS_VALID_VALUES: This view lists all valid values for NLS parameters.

PARAMETER -- VARCHAR2(64)

NLS_* parameter:

LANGUAGE, SORT, TERRITORY, CHARACTERSET

VALUE -- VARCHAR2(64)

NLS_* parameter value

V$OBJECT_DEPENDENCY: This view can be used to determine
what objects are depended on by a package, procedure,
or cursor that is currently loaded in the shared
pool.  For example, together with V$SESSION and
V$SQL, it can be used to determine which tables are used in the
SQL statement that a user is currently executing.

FROM_ADDRESS -- RAW(4)

Address of a procedure, package, or cursor that is currently
loaded in the shared pool

FROM_HASH -- NUMBER

Hash value of a procedure, package, or cursor that is
currently loaded in the shared pool

TO_OWNER -- VARCHAR2(64)

Owner of the object that is depended on

TO_NAME -- VARCHAR2(1000)

Name of the object that is depended on

TO_ADDRESS -- RAW(4)

Address of the object that is depended on.  These can be
used to look up more information on the object in V$DB_
OBJECT_CACHE.

TO_HASH -- NUMBER

Hash number of the object that is depended on. Use this
column to obtain more information from the V$DB_
OBJECT_CACHE table.

TO_TYPE -- NUMBER

Type of the object that is depended on

V$OPEN_CURSOR: Cursors that each user session currently has
opened and parsed

SADDR -- RAW

Session address

SID -- NUMBER

Session identifier. Join this column to V$SESSION to obtain
more information about the session.

USER_NAME -- VARCHAR2

User that is logged into the session

ADDRESS -- RAW

Used with HASH_VALUE to uniquely identify the SQL
statement being executed in the session

HASH_VALUE -- NUMBER

Used with ADDRESS to uniquely identify the SQL statement
being executed in the session

SQL_TEXT -- VARCHAR2

First 60 characters of the SQL statement that is parsed into
the open cursor

V$OPTION: This view lists options that are installed with the Oracle7 server.

PARAMETER -- VARCHAR2(64)

Name of the option

VALUE -- VARCHAR2(64)

TRUE if the option is installed

V$PARAMETER: Information about current INIT.ORA parameter values

NUM -- NUMBER

Parameter number

NAME -- VARCHAR2(64)

Parameter name

TYPE -- NUMBER

Parameter type

VALUE -- VARCHAR2(512)

Parameter value

ISDEFAULT -- VARCHAR2(9)

Default value in use: TRUE, FALSE

V$PING: This is a parallel server view. The V$PING view is identical to
the V$CACHE view but only shows blocks that have been
pinged at least once.  This view contains information from the
block header of each block in the SGA of the current instance as
related to particular database objects.

FILE# -- NUMBER

Data file identifier number (to find filename, query DBA_
DATA_FILES or V$DBFILES)

BLOCK# -- NUMBER

Block number

STATUS -- VARCHAR2(1)

Status of block:

FREE = not currently in use
XCUR = exclusive
SCUR = shared current
CR = consistent read
READ = being read from disk
MREC = in media recovery mode
IREC = in instance recovery mode

XNC -- NUMBER

Number of PCM lock conversions due to contention with
another instance

LOCK_ELEMENT_ADDR -- RAW(4)

Address of the lock element that contains the PCM lock that
is covering the buffer.  If more than one buffer has the
same address, then these buffers are covered by the same
PCM lock.

NAME -- VARCHAR2(30)

Name of the database object containing the block

KIND -- VARCHAR2(12)

Type of database object: TABLE, CLUSTER, INDEX, UNDO = rollback segment

OWNER# -- NUMBER

Owner number

V$PQ_SESSTAT: This view lists session statistics for parallel queries.

STATISTIC -- VARCHAR2(30)

Name of the statistic

LAST_QUERY -- NUMBER

Value of the statistic for the last query

SESSION_TOTAL -- NUMBER

Value of the statistic for the entire session to this point in
time

V$PQ_SLAVE: This view lists statistics for each of the active
parallel query servers on an instance.

SLAVE_NAME -- VARCHAR2(4)

Name of the parallel query server

STATUS -- VARCHAR2(4)

Current status of the parallel query server (BUSY or IDEL)

SESSIONS -- NUMBER

Number of sessions that have used this parallel query
server

IDLE_TIME_CUR -- NUMBER

Amount of time spent idle while processing statements in
the current session

BUSY_TIME_CUR -- NUMBER

Amount of time spent busy while processing statements in
the current session

CPU_SECS_CUR -- NUMBER

Amount of CPU time spent on the current session

MSGS_SENT_CUR -- NUMBER

Number of messages sent while processing statements for
the current session

MSGS_RCVD_CUR -- NUMBER

Number of messages received while processing statements
for the current session

IDLE_TIME_TOTAL -- NUMBER

Total amount of time this query server has been idle

BUSY_TIME_TOTAL -- NUMBER

Total amount of time this query server has been active

CPU_SECS_TOTAL -- NUMBER

Total amount of CPU time this query server has used to
process statements

MSGS_SENT_TOTAL -- NUMBER

Total number of messages this query server has sent

MSGS_RCVD_TOTAL -- NUMBER

Total number of messages this query server has received

V$PQ_SYSSTAT: This view lists system statistics for parallel queries.

STATISTIC -- VARCHAR2(30)

Name of the statistic

VALUE -- NUMBER

Value of the statistic

V$PQ_TQSTAT: This view contains statistics on parallel query operations.
The statistics are compiled after the query completes and remain
only for the duration of the session.  It shows the number of
rows processed through each parallel query server at each stage
of the execution tree.  This view can help to determine skew
problems in a query's execution.

DFO_NUMBER -- NUMBER

Data flow operator (DFO) tree number to differentiate
queries

TQ_ID -- NUMBER

Table queue ID within the query, which represents the
connection between two DFO nodes in the query
execution tree

SERVER_TYPE -- VARCHAR2(10)

Role in table queue - producer / consumer / ranger

NUM_ROWS -- NUMBER

Number of rows produced / consumed

BYTES -- NUMBER

Number of bytes produced / consumed

OPEN_TIME -- NUMBER

Seconds the table queue remained open

AVG_LATENCY -- NUMBER

Time (ms) for a message to be dequeued after it enters the
queue

WAITS -- NUMBER

Number of wits encountered when dequeueing

TIMEOUTS -- NUMBER

Number of timeouts when waiting for a message

PROCESS -- VARCHAR2(10)

Process ID

INSTANCE -- NUMBER

Instance ID

V$PROCESS: Information about currently active processes

ADDR -- RAW(4)

Address of process state object

PID -- NUMBER

Oracle process identifier

SPID -- VARCHAR2

Operating system process identifier

USERNAME -- VARCHAR2

Operating system process username. Any two-task user
coming across the network has "-T" appended to the
username.

SERIAL# -- NUMBER

Process serial number

TERMINAL -- VARCHAR2

Operating system terminal identifier

PROGRAM -- VARCHAR2

Program in progress

BACKGROUND -- VARCHAR2

1 for a background process; null for a normal process

LATCHWAIT -- VARCHAR2

Address of latch waiting for; null if none

LATCHSPIN -- VARCHAR2

Address of latch the process is being spun on; null if none

V$PWFILE_USERS: This view lists users who have been granted SYSDBA and
SYSOPER privileges as derived from the password file.

USERNAME -- VARCHAR2(30)

Name of the user that is contained in the password file

SYSDBA -- VARCHAR2(5)

If the value of this column is TRUE, the user can connect
with SYSDBA privileges

SYSOPER -- VARCHAR2(5)

If the value of this column is TRUE, the user can connect
with SYSOPER privileges

V$QUEUE: Information on the multithread message queue.

PADDR -- RAW(4)

Address of the process that owns the queue

TYPE -- VARCHAR2

Type of queue: COMMON (processed by servers),
OUTBOUND (used by remote servers), DISPATCHER.

QUEUE -- NUMBER

Number of items in the queue

WAIT -- NUMBER

Total time that all items in this queue have waited. Divide
by TOTALQ for average wait per item.

TOTALQ -- NUMBER

Total number of items that have ever been in the queue

V$RECOVERY_LOG: Archived logs needed to complete media recovery. This
information is derived from the log history (V$LOG_HISTORY).
The amount of information available is limited by the setting of
the MAX_LOG_HISTORY intialization parameter.

THREAD# -- NUMBER

Thread number of the archived log

SEQUENCE# -- NUMBER

Sequence number of the archived log

TIME -- VARCHAR2

Time of first entry (lowest SCN) in the log

ARCHIVE_NAME -- VARCHAR2

Name of the file when it is archived, using the naming
convention specified by the LOG_ARCHIVE_FORMAT
initialization   parameter

V$RECOVER_FILE: Status of files needing media recovery

FILE# -- NUMBER

File identifier number

ONLINE -- VARCHAR2

Online status: ONLINE, OFFLINE

ERROR -- VARCHAR2

Why the file needs to be recovered: NULL if reason
unknown, or OFFLINE NORMAL if recovery not needed

CHANGE# -- NUMBER

SCN where recovery must start

TIME -- VARCHAR2

Time of SCN where recovery must start

V$RECOVERY_FILE_STATUS: This view contains one row for each datafile
for each RECOVER command.

FILENUM -- NUMBER

Number of the file being recovered

FILENAME -- VARCHAR2(257)

Filename of the datafile being recovered

STATUS -- VARCHAR2(13)

Status of the recovery

Contains one of the following values: IN RECOVERY, CURRENT, or
NOT RECOVERED

V$RECOVERY_STATUS: This view contains statistics of the current
recovery process.

RECOVERY_CHECKPOINT -- VARCHAR2(20)

Point in time to which the recovery has occurred.  If no
logs have been applied, this is the point in time the
recovery starts

THREAD -- NUMBER

Number of the redo thread currently being processed

SEQUENCE_NEEDED -- NUMBER

Log sequence number of the log needed by the recovery
process.  The value is 0 if no log is needed

SCN_NEEDED -- VARCHAR2(16)

Low SCN of the log needed by recovery.  The value is 0 if
unknown or no log is needed

TIME_NEEDED -- VARCHAR2(20)

Time when the log was created.  The value is midnight on
1/1/88 if the time is unknown or if no log is needed.

PREVIOUS_LOG_NAME -- VARCHAR2(257)

Filename of the log

PREVIOUS_LOG_STATUS -- VARCHAR2(13)

Status of the previous log.  Contains one of the following
values:  RELEASE, WRONG NAME, MISSING NAME,UNNEEDED NAME, or NONE

REASON -- VARCHAR2(13)

Reason recovery is returning control to the user.  Contains
one of the following values: NEED LOG, LOG REUSED, or
THREAD DISABLED

V$REQDIST: Histogram of request times, divided into 12 buckets, or ranges
of time. The time ranges grow exponentially as a function of the
bucket number.

BUCKET -- NUMBER

Bucket number: 0.11; maximum time for each bucket is
(4*2N)/100 seconds

COUNT -- NUMBER

Count of requests whose total time to complete (excluding
wait time) falls in this range.

V$RESOURCE: Information about resources

ADDR -- RAW(4)

Address of resource object

TYPE -- VARCHAR2

Resource type

ID1 -- NUMBER

Resource identifier #1

ID2 -- NUMBER

Resource identifier #2

V$ROLLNAME: Names of all online rollback segments. Join this table
with the V$ROLLSTAT using the USN column table to obtain a collection
of rollback segment performance statistics.

USN -- NUMBER

Rollback ("undo") segment number

NAME -- VARCHAR2

Rollback segment name

V$ROLLSTAT: Statistics for all online rollback segments. Make sure
that your OPTIMAL setting is not set too low. This is identified by the
SHRINKS figure being significant. Another interesting column is
the WAITS column. A small number of waits can often mean a
significant number of transactions have had to wait for the
rollback segments. Consider adding more rollback segments to
get the WAITS figure down to zero.

USN -- NUMBER

Rollback segment number

EXTENTS -- NUMBER

Number of rollback extents

RSSIZE -- NUMBER

Size in bytes of rollback segment

WRITES -- NUMBER

Number of bytes written to rollback segment

XACTS -- NUMBER

Number of active transactions

GETS -- NUMBER

Number of header gets

WAITS -- NUMBER

Number of header waits

OPTSIZE -- NUMBER

Optimal size of rollback segment

HWMSIZE -- NUMBER

High water mark of rollback segment

SHRINKS -- NUMBER

Number of times rollback segment shrank, eliminating one
or more additional extents each time

WRAPS -- NUMBER

Number of times rollback segment wraps from one extent
to another

EXTENDS -- NUMBER

Number of times rollback segment was extended to have a
new extent

AVESHRINK -- NUMBER

Total size of freed extents divided by number of shrinks

AVEACTIVE -- NUMBER

Current average size of active extents, where "active"
extents have uncommitted transaction data

STATUS -- VARCHAR2(15)

ONLINE if the segment is online, or PENDING OFFLINE if
the segment is going offline but some active (distributed)
transactions are using the rollback segment. When the
transactions are complete, the segment goes offline.

CUREXT -- NUMBER

Current extent

CURBLK -- NUMBER

Current block

V$ROWCACHE: Statistics for data dictionary activity. (Each
row contains statistics for one data dictionary cache.)

CACHE# -- NUMBER

Row cache ID number

TYPE -- VARCHAR2

Parent or subordinate row cache type

SUBORDINATE# -- NUMBER

Subordinate set number

PARAMETER -- VARCHAR2

SHARED_POOL_SIZE automatically adjusts the dictionary
cache parameters.

COUNT -- NUMBER

Total number of entries in the cache

USAGE -- NUMBER

Number of cache entries that contain valid data

FIXED -- NUMBER

Number of fixed entries in the cache

GETS -- NUMBER

Total number of requests for information on the data object

GETMISSES -- NUMBER

Number of data requests resulting in cache misses

SCANS -- NUMBER

Number of scan requests

SCANMISSES -- NUMBER

Number of times a scan failed to find the data in the cache

SCANCOMPLETES -- NUMBER

For a list of subordinate entries, the number of times the list
was scanned completely

MODIFICATIONS -- NUMBER

Number of inserts, updates, and deletions

FLUSHES -- NUMBER

Number of times flushed to disk

V$SECONDARY: A Trusted Oracle view that lists secondary mounted databases.
For details, see the Trusted Oracle7 Server Administrator's Guide.

V$SESSION: Session information for each current session. This table contains
a lot of useful tuning information. The LOCKWAIT column
indicates that the user cannot currently access an object because
another user has it locked. You can also obtain the statement
that the user is running by joining the SQL_ADDRESS and SQL_
HASH_VALUE columns with the ADDRESS and HASH_VALUE
columns in the V$SQLAREA table. The V$SESSION also now
contains information on the row being locked.

SADDR -- RAW(4)

Session address

SID -- NUMBER

Session identifier

SERIAL# -- NUMBER

Session serial number. Used to uniquely identify a session's
objects. Guarantees that session-level commands are
applied to the correct session objects in the event that the
session ends and another

AUDSID -- NUMBER

Auditing session ID

PADDR -- RAW(4)

Address of the process that owns this session

USER# -- NUMBER

Oracle user identifier

USERNAME -- VARCHAR2

Oracle user name

COMMAND -- NUMBER

Command in progress; see the command table below

TADDR -- VARCHAR2

Address of transaction state object

LOCKWAIT -- VARCHAR2

Address of lock waiting for; null if none

STATUS -- VARCHAR2

Status of the session: ACTIVE, INACTIVE, KILLED

SERVER -- VARCHAR2

Server type: DEDICATED, SHARED, PSEUDO, NONE

SCHEMA# -- NUMBER

Schema user identifier

SCHEMANAME -- VARCHAR2

Schema user name

OSUSER -- VARCHAR2

Operating system client user name

PROCESS -- VARCHAR2

Operating system client process ID

MACHINE -- VARCHAR2

Operating system machine name

TERMINAL -- VARCHAR2

Operating system terminal name

PROGRAM -- VARCHAR2

Operating system program name

TYPE -- VARCHAR2

Session type

SQL_ADDRESS -- RAW(4)

Used with SQL_HASH_VALUE to identify the SQL statement
that is currently being executed

SQL_HASH_VALUE -- NUMBER

Used with SQL_ADDRESS to identify the SQL statement that
is currently being executed

MODULE -- VARCHAR2(48)

Contains the name of the currently executing module as set
by calling the DBMS_APPLICATION_INFO.SET_MODULE
procedure

MODULE_HASH -- NUMBER

The hash value of the above module_name

ACTION -- VARCHAR2(32)

Contains the name of the currently executing action as set
by calling the dbms_application_info.set_action procedure.

ACTION_HASH -- NUMBER

The hash value of the above action name

CLIENT_INFO -- VARCHAR2(64)

Information set by the DBMS_APPLICATION_INFO.SET_
CLIENT_INFO procedure

FIXED_TABLE_SEQUENCE -- NUMBER

Contains a number that increases every time the session
completes a call to the database and there has been an
intervening select from dynamic performance table.  This
column can be used by performance monitors that  monitor
statistics in the database.  Each time the performance
monitor looks at the database, it needs to look only at
sessions that are currently active or have a higher  value in
this column then the highest value that the performance
monitor saw the last time.  All the other sessions have been
idle since the last time the performance monitor looked at
the database.

ROW_WAIT_OBJ# -- NUMBER

Object ID for the table containing the rowid specified in
ROW_WAIT_ROW#

ROW_WAIT_FILE# -- NUMBER

Identifier for the datafile containing the rowid specified in
ROW_WAIT_ROW#.  This column is valid only if the
session is currently waiting for another transaction to
commit and the value of ROW_WAIT_OBJ# is nonzero

ROW_WAIT_BLOCK# -- NUMBER

Identifier for the block containing the rowid specified in
ROW_WAIT_ROW#.  This column is valid only if the
session is currently waiting for another transaction to
commit and the value of ROW_WAIT_OBJ# is nonzero.

ROW _WAIT_ROW# -- NUMBER

The current rowid being locked.  This column is valid only
if the session is currently waiting for another transaction to
commit and the value of ROW_WAIT_OBJ# is nonzero.

The following table lists numeric values corresponding to
commands that may be in progress during a session.  These
values may appear in the V$SESSION COMMAND column.  They
also appear in the data dictionary view SYS.AUDIT_ACTIONS.

1 CREATE TABLE
2 INSERT
3 SELECT
4 CREATE CLUSTER
5 ALTER CLUSTER
6 UPDATE
7 DELETE
8 DROP
9 CREATE INDEX
10 DROP INDEX
11 ALTER INDEX
12 DROP TABLE
13 -
14 -
15 ALTER TABLE
16 -
17 GRANT
18 REVOKE
19 CREATE SYNONYM
20 DROP SYNONYM
21 CREATE VIEW
22 DROP VIEW
23 -
24 -
25 -
26 LOCK TABLE
27 NO OPERATION
28 RENAME
29 COMMENT
30 AUDIT
31 NOAUDIT
32 CREATE EXTERNAL DATABASE
33 DROP EXTERNAL DATABASE
34 CREATE DATABASE
35 ALTER DATABASE
36 CREATE ROLLBACK SEGMENT
37 ALTER ROLLBACK SEGMENT
38 DROP ROLLBACK SEGMENT
39 CREATE TABLESPACE
40 ALTER TABLESPACE
41 DROP TABLESPACE
42 ALTER SESSION
43 ALTER USER
44 COMMIT
45 ROLLBACK
46 SAVEPOINT

V$SESSION_CONNECT_INFO: This view displays information about
network connections for the current session.

SID -- NUMBER

Session identifier (can be used to join this view with
V$SESSION)

AUTHENTICATION_TYPE -- VARCHAR2(15)

How the user was authenticated: OS, PROTOCOL, or NETWORK.

OSUSER -- VARCHAR2(30)

The external username for this database user

NETWORK_SERVICE_BANNER -- VARCHAR2(2000)

Product banners for each SQL*Net service used for this
connection (one row per banner)

V$SESSION_CURSOR_CACHE: This view displays information on
cursor usage for the current session.

SID -- NUMBER

Session identifier

MAXIMUM -- NUMBER

Maximum number of cursors to cache.  Once you hit this
number, some cursors will need to be closed to open more.

COUNT-- NUMBER

Current number of cursors (in use or not)

OPENED_ONCE -- NUMBER

Number of cursors opened at least once

OPEN -- NUMBER

Current number of open cursors

OPENS -- NUMBER

Cumulative total of cursor opens

HITS -- NUMBER

Cumulative total of cursor open hits

HIT_RATIO -- NUMBER

Ratio of the number of times we found an open cursor
divided by the number of times we looked for a cursor

V$SESSION_EVENT: This view lists information on waits for an event by
a session.  Note that the TIME_WAITED and AVERAGE_WAIT columns will
contain a value of zero on those platforms that do not support a
fast timing mechanism.  If you are running on one of these
platforms and you wish this column to reflect true wait times,
you must set TIMED_STATISTICS to TRUE in the parameter file.
Please remember that doing this will have a small negative effect
on system performance.

SID -- NUMBER

The ID of the session

EVENT -- VARCHAR2(64)

The name of the wait event

TOTAL_WAITS -- NUMBER

The total number of waits for this event by this session

TOTAL_TIMEOUTS -- NUMBER

The total number of timeouts for this event by this session

TIME_WAITED -- NUMBER

The total amount of time waited for this event by this
session, in hundredths of a second

AVERAGE_WAIT -- NUBMER

The average amount of time waited for this event by this
session, in hundredths of a second

V$SESSION_WAIT: This view lists the resources
or events for which active sessions
are waiting . Many DBAs find this table useful to obtain a
snapshot of any waits that are occurring on the database at any
given point in time. Join the SID with the column of the same
name in the V$SESSION event to obtain the users name, as well
as other useful information. The following are tuning
considerations:

P1RAW, P2RAW, and P3RAW display the same values as the P1,
P2, and P3 columns, except that the numbers are displayed in
hex.

The WAIT_TIME column contains a value of minus 2 on
platforms that do not support a fast timing mechanism.  If you
are running on one of these platforms and you wish this column
to reflect true wait times, you must set the TIMED_STATISTICS
parameters to TRU.  Remember that doing this has a small
negative effect on system performance.

In previous releases, the WAIT_TIME column contained an
arbitrarily large value instead of a negative value to indicate the
platform did not have a fast timing mechanism.

The STATE column interprets the value of WAIT_TIME and
describes the state of the current or most recent wait.

SID -- NUMBER

Session identifier

SWQ# -- NUMBER

Sequence number that uniquely identifies this wait.
Increments for each wait.

EVENT -- VARCHAR2

Resource or event the session is waiting for

P1TEXT -- VARCHAR2

Description of first additional parameter

P1 -- NUMBER

First additional parameter

P1RAW -- RAW(4)

More information on first parameter

P2TEXT -- VARCHAR2

Description of second parameter

P2 -- NUMBER

Second additional parameter

P2RAW -- RAW(4)

More information on second parameter

P3TEXT -- VARCHAR2

Description of third parameter

P3 -- NUMBER

Third additional parameter

P3RAW -- RAW(4)

More information on third parameter

WAIT_TIME -- NUMBER

A nonzero value is the session's last wait time. A zero value
means that the session is currently waiting.

STATE -- VARCHAR2

Wait state (see following table)

V$SESSTAT: For each current session, the current statistics values.

SID -- NUMBER

Session identifier

STATISTIC# -- NUMBER

Statistic number (identifier)

VALUE -- NUMBER

Statistic value

V$SESS_IO: I/O statistics for each user session. You can obtain the
individual users hit ratios from joining this table to the
V$SESSION using the SID column. If one user has a poor hit
ratio, you must find out the SQL that they have been running.

SID -- NUMBER

Session identifier

BLOCK_GETS -- NUMBER

Block gets for this session

CONSISTENT_GETS -- NUMBER

Consistent gets for this session

PHYSICAL_READS -- NUMBER

Physical reads for this session

BLOCK_CHANGES -- NUMBER

Block changes for this session

CONSISTENT_CHANGES# -- NUMBER

Consistent changes for this session

V$SGA: Summary information on the System Global Area.

NAME -- VARCHAR2

SGA component group

VALUE -- NUMBER

Memory size in bytes

V$SGASTAT: Detailed information on the System Global Area.

NAME -- VARCHAR2

SGA component name

BYTES -- NUMBER

Memory size in bytes

V$SHARED_POOL_RESERVED: This fixed view lists statistics
that help you to tune the reserved
pool and space within the shared pool. The following columns
of V$SHARED_POOL_RESERVED are valid only if the
intialization parameter SHARED_POOL_RESERVED_SIZE is set to
a valid value.

FREE_SPACE -- NUMBER

Total amount of free space on the reserved list

AVG_FREE_SIZE -- NUMBER

Average size of the free memory on the reserve list

FREE_COUNT -- NUMBER

Number of free pieces of memory on the reserved list

MAX_FREE_SIZE -- NUMBER

Size of the largest free piece of memory on the reserved list

USED_SPACE -- NUMBER

Total amount of used memory on the reserved list

AVG_USED_SIZE -- NUMBER

Average size of the used memory on the reserved list

USED_COUNT -- NUMBER

Number of used pieces of memory on the reserved list

MAX_USED_SIZE -- NUMBER

Size of the largest used piece of memory on the reserved
list

REQUESTS -- NUMBER

Number of times that the reserved listed was searched for a
free piece of memory

REQUEST_MISSES -- NUMBER

Number of times the reserved list did not have a free piece
of memory to satisfy the request, and started flushing
objects from the LRU list

LAST_MISS_SIZE -- NUMBER

Request size of the last request miss, when the reserve list
did not have a free piece of memory to satisfy the request
and started flushing objects from the LRU list

MAX_MISS_SIZE -- NUMBER

Request size of the largest request miss, when the reserved
list did not have a free piece of memory to satisfy the
request the started flushing objects from the LRU list

The following columns of V$SHARED_POOL_RESERVED
contains values that are valid even if SHARED_POOL_
RESERVED_SIZE is not set.

REQUEST_FAILURES -- NUMBER

Number of times that no memory was found to satisfy a
request (that is, the number of times the error ORA-4031
occurred)

LAST_FAILURE_SIZE -- NUMBER

Request size of the last failed request (that is, the request
size for the last ORA-4031 error)

ABORTED_REQUEST_THRESHOLD -- NUMBER

Minimum size of request that signals an ORA-4031 error
without flushing objects

ABORTED_REQUSTS -- NUMBER

Number of requests that signaled an ORA-4031 error
without flushing objects

LAST_ABORTED_SIZE -- NUMBER

Last size of the request that returned an ORA_4031 error
without flushing objects from the LRU list

V$SHARED_SERVER: Information on the shared server processes

NAME -- VARCHAR2

Name of the server

PADDR -- RAW(4)

Server's process address

STATUS -- VARCHAR2

Server status: EXEC (executing SQL),
WAIT (ENQ) (waiting for a lock),
WAIT (SEND) (waiting to send data to user),
WAIT (COMMON) (idle; waiting for a user request),
WAIT (RESET) (waiting for a circuit to reset after a break),
QUIT (terminating)

MESSAGES -- NUMBER

Number of messages processed

BYTES -- NUMBER

Total number of bytes in all messages

BREAKS -- NUMBER

Number of breaks

CIRCUIT -- RAW(4)

Address of circuit currently being serviced

IDLE -- NUMBER

Total idle time in hundredths of a second

BUSY -- NUMBER

Total busy time in hundredths of a second

REQUESTS -- NUMBER

Total number of requests taken from the common queue in
this server's lifetime

V$SORT_SEGMENT: This view contains information about every sort
segment in a given instance.

TABLESPACE_NAME - VARCHAR2(31)

Name of tablespace

SEGMENT_FILE -- NUMBER

File number of the first extent

SEGMENT_BLOCK -- NUMBER

Block number of the first extent

EXTENT_SIZE -- NUMBER

Extent size

CURRENT_USERS -- NUMBER

Number of active users of the segment

TOTAL_EXTENTS -- NUMBER

Total number of extents in the segment

TOTAL_BLOCKS -- NUMBER

Total number of blocks in the segment

USED_EXTENTS -- NUMBER

Extents allocated to active sorts

USED_BLOCKS -- NUMBER

Blocks allocated to active sorts

FREE_EXTENTS -- NUMBER

Extents not allocated to any sort

FREE_BLOCKS -- NUMBER

Blocks not allocated to any sort

ADDED_EXTENTS -- NUMBER

Number of extent allocations

EXTENT_HITS -- NUMBER

Number of times an unused extent was found in the pool

FREE_EXTENTS -- NUMBER

Number of deallocated extents

FREE_REQUESTS -- NUMBER

Number of requests of deallocate

MAX_SIZE -- NUMBER

Maximum number of extents ever used

MAX_BLOCKS -- NUMBER

Maximum number of blocks ever used

MAX_USED_SIZE -- NUMBER

Maximum number of blocks used by all sorts

MAX_SORT_SIZE -- NUMBER

Maximum number of extents used by an individual sort

MAX_SORT_BLOCKS -- NUMBER

Maximum number of blocks used by an individual sort

V$SQL: This view lists statistics on shared SQL area without the GROUP
BY clause and contains one row for each child of the original
SQL text entered.

SQL_TEXT -- VARCHAR2(1000)

The first 80 characters of the SQL text for the current cursor

SHARABLE_MEM -- NUMBER

Sum of all sharable memory, in bytes, of all the child
cursors under this parent

PERSISTENT_MEM -- NUMBER

Sum of all persistent memory, in bytes, of all the child
cursors under this parent

RUNTIME_MEM -- NUMBER

Sum of all the ephemeral frame sizes of all the children

SORTS -- NUMBER

Sum of the number of sorts that was done for all the
children

LOADED_VERSIONS -- NUMBER

Number of children that are present in the cache AND have
their context heap 9KGL heap 6) loaded

OPEN_VERSIONS -- NUMBER

Number of child cursors that are currently open under this
current this parent

USERS_OPENING -- NUMBER

Number of users that have any of the child cursors open

EXECUTIONS -- NUMBER

Number of executions that tool place on this object since it
was brought into the library cache

USERS_EXECUTING -- NUBMER

Sum of all users executing the statement over all children

LOADS -- NUMBER

Number of times the object was loaded or reloaded

FIRST_LOAD_TIME -- VARCHAR2(19)

Time stamp of the parent creation time

INVALIDATIONS -- NUMBER

Sum of invalidations over all the children

PARSE_CALLS -- NUMBER

Sum of all parse calls to all the child cursors under this
parent

DISK_READS -- NUMBER

Sum of the number of disk reads over all child cursors

BUFFER_GETS -- NUMBER

Sum of buffer gets over all child cursors

POWS_PROCESSED -- NUMBER

Total number of rows the parsed SQL statement returns

COMMAND_TYPE -- NUMBER

Oracle command type definition

OPTIMIZER_MODE -- VARCHAR2(10)

OPTIMZER used to execute the SQL statement

PARSING_USER_ID -- NUMBER

User ID of the user that has parsed the very first cursor
under this parent

PARSING_SCHEMA_ID -- NUMBER

Schema ID that was used to parse this child cursor

KEPT_VERSIONS -- NUMBER

Number of child cursors that have been marked to be kept
using the DBMS_SHARED_POOL package

ADDRESS -- RAW(4)

Address of the handle to the parent for this cursor

HASH_VALUE -- NUMBER

Hash value of the parent statement in the library cache

CHILD_NUMBER -- NUMBER

Number of child of the original SQL text, beginning from 0

MODULE -- VARCHAR2(64)

Contains the name of the module that was executing at the
time that the SQL statement was first parsed as set by
calling DBMS_APPLICATION_INFO.SET_MODULE

MODULE_HASH -- NUMBER

The has value of the module that is named in the MODULE
column

ACTION -- VARCHAR2(64)

Contains the name of the action that was executing at the
time that the SQL statement was first parsed as set by
calling SBMS_APPLICATION_INFO. SET_ACTION

ACTION_HASH -- NUMBER

Hash value of the action that is named in the action column

SERIALIZABLE_ABORTS -- NUMBER

Number of times the transaction fails to serialize, producing
ORA_8177 errors, per cursor

V$SQLAREA: Statistics on the shared cursor cache. Each row has statistics
on one shared cursor. One useful piece of information  for OLTP
applications is to obtain the SQL_TEXT where  DISK_READS /
EXECUTIONS / 50 > 3.  Assuming 50 I/Os per second, the
computation will give you all of teh SQL statements that will
give the users a response time greater that 3 seconds.

SQL_TEXT -- VARCHAR2(1000)

Text of the SQL statement requiring the cursor, or the
PL/SQL anonymous code

SHARABLE_MEM -- NUMBER

Amount of memory in bytes that is sharable between users

PERSISTENT_MEM -- NUMBER

Amount of per-user memory in bytes that persists for the
life of the cursor

RUNTIME_MEM -- NUMBER

Amount of pre-user memory, in bytes, that is needed only
during execution

SORTS -- NUMBER

Number of sorts performed by the SQL statement.

VERSION_COUNT -- NUMBER

Number of different versions of this cursor. The same SQL
text might be used by different users, each on their own
version of a table (for example, "SELECT* from EMP" by
SCOTT and JONES, when they each have their own version
of EMP). In that case, multiple versions of the cursor would
exist.

LOADED_VERSIONS -- NUMBER

Versions of the cursor that are currently fully loaded, with
no parts aged out

OPEN_VERSIONS -- NUMBER

Number of versions that some user has an open cursor on.

USERS_OPENING -- NUMBER

Number of users that currently have this SQL statement
parsed in an open cursor

EXECUTIONS -- NUMBER

Total number of times this SQL statement has been
executed

USERS_EXECUTING -- NUMBER

Number of users that are currently executing this cursor

LOADS -- NUMBER

Number of times the cursor has been loaded after the body
of the cursor has been aged out of the cache while the text
of the SQL statement remained in it, or after the cursor is
invalidated

FIRST_LOAD_TIME -- VARCHAR2(19)

Loaded into the SGA

INVALIDATIONS -- NUMBER

Number of times the contents of the cursor have been
invalidated. For example: because tables referenced in the
cursor are dropped, validated, or indexed

PARSE_CALLS -- NUMBER

Number of times users executed a parse call for this cursor

DISK_READS -- NUMBER

Number of disk blocks read by this cursor and all cursors
caused to be executed by this cursor

BUFFER_GETS -- NUMBER

Number of buffers gotten (in any mode) by this cursor and
all cursors caused to be executed by this cursor

ROWS_PROCESSED -- NUMBER

Total number of rows returned by the statement

COMMAND_TYPE -- NUMBER

See the codes listed following the V$SESSION description.
The most common codes are 2 for INSERT, 3 for SELECT, 6
for UPDATE and 7 for DELETE.

OPTIMIZER_MODE -- VARCHAR2(10)

RULE, CHOOSE, FIRST_ROWS or ALL_ROWS

PARSING_USER_ID -- NUMBER

User that parsed the statement the first time the statement
was run. Join this column to the USER# in V$SESSION.

PARSING_SCHEMA_ID -- NUMBER

Schema ID that was used for the initial parse

KEPT_VERSIONS -- NUMBER

Number of child versions that have been pinned in the
library cache using the DBMS_SHARED_POOL package.

ADDRESS -- RAW

Used together with HASH_VALUE to select the full text of
the SQL statement from V$SQLTEXT

HASH_VALUE -- NUMBER

Used together with ADDRESS to select the full text of the
SQL statement from V$SQLTEXT

MODULE -- VARCHAR2(64)

Contains the name of the module that was executing at the
time that the SQL statement was first parsed as set by
calling DBMS_APPLICATION_INFO.SET_MODULE

MODULE_HASH -- NUMBER

The hash value of the module that is named in the
MODULE column

ACTION -- VARCHAR2(64)

Contains the name of the action that was executing at the
time that the SQL statement was first parsed as set by
calling DBMS_APPLICATION_INFO.SET_ACTION

ACTION_HASH -- NUMBER

Hash value of the action that is named in the ACTION
column

SERIALIZABLE_ABORTS -- NUMBER

Number of times the transaction fails to serialize, producing
ORA-8177 errors, per cursor

V$SQLTEXT: The text of SQL statements belonging to shared SQL cursors in
the SGA

ADDRESS -- RAW

Used with HASH_VALUE to uniquely identify a cached
cursor

HASH_VALUE -- NUMBER

Used with ADDRESS to uniquely identify a cached cursor

PIECE -- NUMBER

Number used to order the pieces of SQL text

SQL_TEXT -- VARCHAR2

A column containing one piece of the SQL text

COMMAND_TYPE -- NUMBER

Code for the type of SQL statement (9SELECT, INSERT, etc.)

V$SQLTEXT_WITH_NEWLINES: This view is identical to
the V$SQLTEXT view except that to
improve legibility, V$SQLTEXT_WITH_NEWLINES does not
replace new lines and tabs in the SQL statement with spaces.

ADDRESS -- RAW

Used with HASH_VALUE to identify uniquely a cached
cursor

HASH_VALUE -- NUMBER

Used with ADDRESS to identify uniquely a cached cursor

PEICE -- NUMBER

Number used to order the pieces of SQL text

SQL_TEXT -- VARCHAR2

Column contains one piece of the SQL text

COMMAND_TYPE -- NUMBER

Code for the type of SQL statement (SELECT, INSERT, etc.)

V$STATNAME: Decoded statistic names for the statistics shown in the
V$SESSTAT table

STATISTIC# -- NUMBER

Statistic number

NAME -- VARCHAR2

Statistic name

CLASS -- NUMBER

Statistic class: 1 (User), 2 (Redo), 4 (Enqueue), 8 (Cache),
16 (OS), 32 (Parallel Server), 64 (SQL), 128 (Debug)

V$SYSLABEL: A Trusted Oracle view that lists system labels. For details,
see the Trusted Oracle7 Server Administrator's Guide.

V$SYSSTAT: The current systemwide value for each statistic in table
V$SESSTAT.

STATISTIC# -- NUMBER

Statistic number

NAME -- VARCHAR2

Statistic name

CLASS -- NUMBER

Statistic class: 1 (User), 2 (Redo), 4 (Enqueue), 8 (Cache)

VALUE -- NUMBER

Statistic value

V$SYSTEM_CURSOR_CACHE: This view displays similar information
to V$SESSION_CURSOR_ CACHE view except that this information is systemwide.

OPENS -- NUBMER

Cumulative total of cursor opens

HITS -- NUMBER

Cumulative total of cursor open hits

HIT_RATIO -- NUMBER

Ratio of the number of times you found an open cursor
divided by the number of times you looked for a cursor

V$SYSTEM_EVENT -- This view contains information on total waits for
an event.  Note that the TIME_WAITED and AVERAGE_WAIT columns will
contain a value of zero on those platforms that do not support a
fast timing mechanism.  If you are running on one of these
platforms and you wish this column to reflect true wait times,
you must set TIMED_STATISTICS to TRUE in the parameters
file.  Please remember that doing this will have a small negative
effect on system performance.

EVENT -- VARCHAR2(64)

The name of the wait event

TOTAL_WAITS -- NUMBER

The total number of waits for this event

TOTAL_TIMEOUTS -- NUMBER

The total number of timeouts for this event

TIME_WAITED -- NUMBER

The total amount of time waited for this event, in
hundredths of a second

AVERAGE_WAIT -- NUMBER

The average amount of time waited for this event, in
hundredths of a second

V$SYSTEM_PARAMETER: This view contains information on system parameters.

V$THREAD: Thread information from the control file

THREAD# -- NUMBER

Thread number

STATUS -- VARCHAR2

Thread status: OPEN, CLOSED

ENABLED -- VARCHAR2

Enabled status: DISABLED, (enabled) PRIVATE, or
(enabled) PUBLIC

GROUPS -- NUMBER

Number of log groups assigned to this thread

INSTANCE -- VARCHAR2

Instance name, if available

OPEN_TIME --  VARCHAR2

Last time the thread was opened

CURRENT_GROUP# -- NUMBER

Current log group

SEQUENCE# -- NUMBER

Sequence number of current log

CHECKPOINT_CHANGE# -- NUMBER

SCN at last checkpoint

CHECKPOINT_TIME -- VARCHAR2

Time of last checkpoint

V$TIMER: The current time in hundredths of seconds

HSECS -- NUMBER

Time in hundredths of a second

V$TRANSACTION: Information about transactions

ADDR -- RAW(4)

Address of transaction state object

XIDUSN -- NUMBER

Rollback (undo) segment number; invalid if inactive

XIDSLOT -- NUMBER

Slot number; invalid if inactive

XIDSQN -- NUMBER

Sequence number; invalid if inactive

UBAFIL -- NUMBER

Undo block address (UBA) filenum, invalid if inactive

UBABLK -- NUMBER

Undo block number, invalid if inactive

UBASQN -- NUMBER

Sequence number for rollback data; invalid if inactive

UBAREC -- NUMBER

Record number for rollback data; invalid if inactive

STATUS -- VARCHAR2(16)

Status

START_TIME -- VARCHAR2(20)

Start time

START_SCNB - NUMBER

Start system change number SCN base

START_SCNW -- NUMBER

Start SCN wrap

START_UEXT -- NUMBER

Start extent number

START_UBAFIL -- NUMBER

Start UBA file number

START_UBABLK -- NUMBER

Start UBA block number

START_UBASQN -- NUMBER

Start UBA sequence number

START_UBAREC -- NUMBER

Start UBA record number

SES_ADDR -- RAW(4)

Session object address

FLAG -- NUMBER

Flag

SPACE -- VARCHAR2(3)

Is a space transaction

RECURSIVE -- VARCHAR2(3)

Is a recursive transaction

NOUNDO -- VARCHAR2(3)

Is a noundo transaction

PRV_XIDUSN -- NUMBER

Parent transaction ID

PRV_XIDSLT -- NUMBER

Parent transaction slot number

PRV_XIDSQN -- NUBMER

Parent transaction sequence number

USED_UBLK -- NUMBER

Undo blocks used

USED_UREC -- NUMBER

Undo record used

LOG_IO -- NUMBER

Logical I/O

PHY_IO -- NUMBER

Physical I/O

GR_GET -- NUMBER

Consistent gets

CR_CHANGE -- NUMBER

Consistent changes

V$TYPE_SIZE: Sizes of various database components for use in
estimating data block capacity

COMPONENT -- VARCHAR2

Component name, such as segment or buffer header

TYPE -- VARCHAR2

Component type

DESCRIPTION -- VARCHAR2

Description of component

SIZE -- NUMBER

Size of component

V$VERSION: Version numbers of core library components in the Oracle
Server. There is one row for each component.

BANNER -- VARCHAR2

Component name and version number

V$WAITSTAT: Block contention statistics. This table is updated only when
timed statistics are enabled.

CLASS -- VARCHAR2

Class of block subject to contention. If the count for the class "undo
header" is high, you should be adding rollback segments.

COUNT -- NUMBER

Number of waits by this OPERATION for this CLASS of block

TIME -- NUMBER

Sum of all wait times for all the waits by this OPERATION for this
CLASS of block


Oracle7.3 Performance Table Usage:

System-wide information:

V$PARAMETER
V$SGA
V$SGASTAT
V$SORT_SEGMENT
V$SQL
V$SQLAREA
V$SQLTEXT
V$SQLTEXT_WITH_NEWLINES
V$STATNAME
V$SYSSTAT
V$SYSTEM_CURSOR_CACHE
V$SYSTEM_EVENT

Transaction information:

V$DB_LINK
V$LOCKED_OBJECT
V$SESSION
V$SQLSAREA
V$SQLTEXT
V$SQLTEXT_WITH_NEWLINES
V$TRANSACTION

Parallel query:

V$PQ_SESSTAT
V$PQ_SLAVE
V$PQ_SYSSTAT
V$PQ_TQSTAT

CPU information:

V$SESSTAT
V$SQL
V$SQLAREA
V$SYSSTAT
V$TRANSACTION

Session information:

V$ACCESS
V$LATCH_HOLDER
V$LOCK
V$LOCKED_OBJECT_MYSTAT
V$OPEN_CURSOR_PROCESS
V$SESSION
V$SESSION_CONNECT_INFO
V$SESSION_WAIT
V$SESSTAT
V$SESS_IO

Multithreaded server:

V$CIRCUIT
V$DISPATCHER
V$QUEUE
V$SHARED_SERVER
V$SESSION

Parallel server:

V$BH
V$CACHE
V$CACHE_LOCK
V$FALSE_PING
V$LOCK_ACTIVITY
V$LOCK_ELEMENT
V$LOCKS_WITH_COLLISIONS
V$PING

Packages, procedures, triggers:

V$DB_OBJECT_CACHE
V$LIBRARY_CACHE
V$SHARED_POOL_RESERVED_SIZE
V$SQL
V$SQLAREA

Disk I/O information:

V$DATAFILE
V$FILESTAT
V$ROLLSTAT
V$SESSTAT
V$SESS_IO
V$SORT_SEGMENT
V$SQL
V$SQLAREA
V$SYSSTAT
V$TRANSACTION

Memory information:

V$BH
V$CACHE
V$LIBRARY_CACHE
V$DB_OBJECT_CACHE
V$ROWCACHE
V$SESSTAT
V$SGA
V$SHARED_POOL_RESERVED_SIZE
V$SQL
V$SQLAREA
V$SYSSTAT
V$SYSTEM_CURSOR_CACHE

Locking and contention:

V$LATCH
V$LATCHHOLDER
V$LATCHNAME
V$LATCH_CHILDREN
V$LATCHMISSES
V$LATCHPARENT
V$LOCK
V$LIBRARY_CACHE
V$DB_OBJECT_CACHE
V$PROCESS
V$ROLLSTAT
V$SESSION
V$SESSION_EVENT
V$SESSION_WAIT
V$SHARED_POOL_RESERVED_SIZE
V$SYSTEM_EVENT
V$WAITSTAT