oracle官方文档之V$SESSION

V$SESSION V$SESSION displays session information for each current session. Column Datatype Description SADDR RAW(4 | 8) Session address SID NUMBER Session identifier SERIAL# NUMBER Session serial number. Used to uniquely identify a session

V$SESSION

V$SESSION displays session information for each current session.

Column	Datatype	Description
SADDR	RAW(4 | 8)	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 if the session ends and another session begins with the same session ID.
AUDSID	NUMBER	Auditing session ID
PADDR	RAW(4 | 8)	Address of the process that owns the session
USER#	NUMBER	Oracle user identifier
USERNAME	VARCHAR2(30)	Oracle username
COMMAND	NUMBER	Command in progress (last statement parsed). You can find the command name for any value n returned in this COMMAND column by running this SQL query: SELECT command_name FROM v$sqlcommand WHERE command_type = n; A value of 0 in this COMMAND column means the command is not recorded in V$SESSION.
OWNERID	NUMBER	Identifier of the user who owns the migratable session; the column contents are invalid if the value is 2147483644 For operations using Parallel Slaves, interpret this value as a 4-byte value. The low-order 2 bytes represent the session number and the high-order bytes represent the instance ID of the query coordinator.
TADDR	VARCHAR2(8)	Address of the transaction state object
LOCKWAIT	VARCHAR2(8)	Address of the lock the session is waiting for; NULL if none
STATUS	VARCHAR2(8)	Status of the session: ACTIVE - Session currently executing SQL INACTIVE - Session which is inactive and either has no configured limits or has not yet exceeded the configured limits KILLED - Session marked to be killed CACHED - Session temporarily cached for use by Oracle*XA SNIPED - An inactive session that has exceeded some configured limits (for example, resource limits specified for the resource manager consumer group or idle_time specified in the user's profile). Such sessions will not be allowed to become active again.
SERVER	VARCHAR2(9)	Server type: DEDICATED SHARED PSEUDO POOLED NONE
SCHEMA#	NUMBER	Schema user identifier
SCHEMANAME	VARCHAR2(30)	Schema user name
OSUSER	VARCHAR2(30)	Operating system client user name
PROCESS	VARCHAR2(24)	Operating system client process ID
MACHINE	VARCHAR2(64)	Operating system machine name
PORT	NUMBER	Client port number
TERMINAL	VARCHAR2(30)	Operating system terminal name
PROGRAM	VARCHAR2(48)	Operating system program name
TYPE	VARCHAR2(10)	Session type
SQL_ADDRESS	RAW(4 | 8)	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
SQL_ID	VARCHAR2(13)	SQL identifier of the SQL statement that is currently being executed
SQL_CHILD_NUMBER	NUMBER	Child number of the SQL statement that is currently being executed
SQL_EXEC_START	DATE	Time when the execution of the SQL currently executed by this session started; NULL if SQL_ID is NULL
SQL_EXEC_ID	NUMBER	SQL execution identifier; NULL if SQL_ID is NULL or if the execution of that SQL has not yet started (see V$SQL_MONITOR)
PREV_SQL_ADDR	RAW(4 | 8)	Used with PREV_HASH_VALUE to identify the last SQL statement executed
PREV_HASH_VALUE	NUMBER	Used with SQL_HASH_VALUE to identify the last SQL statement executed
PREV_SQL_ID	VARCHAR2(13)	SQL identifier of the last SQL statement executed
PREV_CHILD_NUMBER	NUMBER	Child number of the last SQL statement executed
PREV_EXEC_START	DATE	SQL execution start of the last executed SQL statement
PREV_EXEC_ID	NUMBER	SQL execution identifier of the last executed SQL statement
PLSQL_ENTRY_OBJECT_ID	NUMBER	Object ID of the top-most PL/SQL subprogram on the stack; NULL if there is no PL/SQL subprogram on the stack
PLSQL_ENTRY_SUBPROGRAM_ID	NUMBER	Subprogram ID of the top-most PL/SQL subprogram on the stack; NULL if there is no PL/SQL subprogram on the stack
PLSQL_OBJECT_ID	NUMBER	Object ID of the currently executing PL/SQL subprogram; NULL if executing SQL
PLSQL_SUBPROGRAM_ID	NUMBER	Subprogram ID of the currently executing PL/SQL object; NULL if executing SQL
MODULEFoot 1	VARCHAR2(48)	Name of the currently executing module as set by calling the DBMS_APPLICATION_INFO.SET_MODULE procedure
MODULE_HASH	NUMBER	Hash value of the MODULE column
ACTIONFootref 1	VARCHAR2(32)	Name of the currently executing action as set by calling the DBMS_APPLICATION_INFO.SET_ACTION procedure
ACTION_HASH	NUMBER	Hash value of the ACTION column
CLIENT_INFO	VARCHAR2(64)	Information set by the DBMS_APPLICATION_INFO.SET_CLIENT_INFO procedure
FIXED_TABLE_SEQUENCE	NUMBER	This contains a number that increases every time the session completes a call to the database and there has been an intervening select from a dynamic performance table. This column can be used by performance monitors to monitor statistics in the database. Each time the performance monitor looks at the database, it only needs to look at sessions that are currently active or have a higher value in this column than 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 row specified in ROW_WAIT_ROW#
ROW_WAIT_FILE#	NUMBER	Identifier for the datafile containing the row 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 not -1.
ROW_WAIT_BLOCK#	NUMBER	Identifier for the block containing the row 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 not -1.
ROW_WAIT_ROW#	NUMBER	Current row 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 not -1.
TOP_LEVEL_CALL#	NUMBER	Oracle top level call number
LOGON_TIME	DATE	Time of logon
LAST_CALL_ET	NUMBER	If the session STATUS is currently ACTIVE, then the value represents the elapsed time (in seconds) since the session has become active. If the session STATUS is currently INACTIVE, then the value represents the elapsed time (in seconds) since the session has become inactive.
PDML_ENABLED	VARCHAR2(3)	This column has been replaced by the PDML_STATUS column
FAILOVER_TYPE	VARCHAR2(13)	Indicates whether and to what extent transparent application failover (TAF) is enabled for the session: NONE - Failover is disabled for this session SESSION - Client is able to fail over its session following a disconnect SELECT - Client is able to fail over queries in progress as well See Also: Oracle Database Concepts for more information on TAF Oracle Database Net Services Administrator's Guide for information on configuring TAF
FAILOVER_METHOD	VARCHAR2(10)	Indicates the transparent application failover method for the session: NONE - Failover is disabled for this session BASIC - Client itself reconnects following a disconnect PRECONNECT - Backup instance can support all connections from every instance for which it is backed up
FAILED_OVER	VARCHAR2(3)	Indicates whether the session is running in failover mode and failover has occurred (YES) or not (NO)
RESOURCE_CONSUMER_GROUP	VARCHAR2(32)	Name of the session's current resource consumer group
PDML_STATUS	VARCHAR2(8)	If ENABLED, the session is in a PARALLEL DML enabled mode. If DISABLED, PARALLEL DML enabled mode is not supported for the session. If FORCED, the session has been altered to force PARALLEL DML.
PDDL_STATUS	VARCHAR2(8)	If ENABLED, the session is in a PARALLEL DDL enabled mode. If DISABLED, PARALLEL DDL enabled mode is not supported for the session. If FORCED, the session has been altered to force PARALLEL DDL.
PQ_STATUS	VARCHAR2(8)	If ENABLED, the session is in a PARALLEL QUERY enabled mode. If DISABLED, PARALLEL QUERY enabled mode is not supported for the session. If FORCED, the session has been altered to force PARALLEL QUERY.
CURRENT_QUEUE_DURATION	NUMBER	If queued (1), the current amount of time the session has been queued. If not currently queued, the value is 0.
CLIENT_IDENTIFIER	VARCHAR2(64)	Client identifier of the session
BLOCKING_SESSION_STATUS	VARCHAR2(11)	This column provides details on whether there is a blocking session: VALID - there is a blocking session, and it is identified in the BLOCKING_INSTANCE and BLOCKING_SESSION columns NO HOLDER - there is no session blocking this session NOT IN WAIT - this session is not in a wait UNKNOWN - the blocking session is unknown
BLOCKING_INSTANCE	NUMBER	Instance identifier of the blocking session. This column is valid only if BLOCKING_SESSION_STATUS has the value VALID.
BLOCKING_SESSION	NUMBER	Session identifier of the blocking session. This column is valid only if BLOCKING_SESSION_STATUS has the value VALID.
FINAL_BLOCKING_SESSION_STATUS	VARCHAR2(11)	The final blocking session is the final element in the wait chain constructed by following the sessions that are blocked by one another starting with this session. In the case of a cyclical wait chain, one of the sessions in the wait chain will be chosen as the final blocker. This column provides details on whether there is a final blocking session: VALID - there is a final blocking session and it is identified in the FINAL_BLOCKING_INSTANCE and FINAL_BLOCKING_SESSION columns NO HOLDER - there is no session blocking this session NOT IN WAIT - this session is not in a wait UNKNOWN - the final blocking session is unknown
FINAL_BLOCKING_INSTANCE	NUMBER	Instance identifier of the final blocking session. This column is valid only if FINAL_BLOCKING_SESSION_STATUS has the value VALID.
FINAL_BLOCKING_SESSION	NUMBER	Session identifier of the blocking session. This column is valid only if FINAL_BLOCKING_SESSION_STATUS has the value VALID.
SEQ#	NUMBER	A number that uniquely identifies the current or last wait (incremented for each wait)
EVENT#	NUMBER	Event number
EVENT	VARCHAR2(64)	Resource or event for which the session is waiting See Also: Appendix C, "Oracle Wait Events"
P1TEXT	VARCHAR2(64)	Description of the first wait event parameter
P1	NUMBER	First wait event parameter (in decimal)
P1RAW	RAW(8)	First wait event parameter (in hexadecimal)Foot 2
P2TEXT	VARCHAR2(64)	Description of the second wait event parameter
P2	NUMBER	Second wait event parameter (in decimal)
P2RAW	RAW(8)	Second wait event parameter (in hexadecimal)Footref 2
P3TEXT	VARCHAR2(64)	Description of the third wait event parameter
P3	NUMBER	Third wait event parameter (in decimal)
P3RAW	RAW(8)	Third wait event parameter (in hexadecimal)Footref 2
WAIT_CLASS_ID	NUMBER	Identifier of the class of the wait event
WAIT_CLASS#	NUMBER	Number of the class of the wait event
WAIT_CLASS	VARCHAR2(64)	Name of the class of the wait event
WAIT_TIME	NUMBER	If the session is currently waiting, then the value is 0. If the session is not in a wait, then the value is as follows: > 0 - Value is the duration of the last wait in hundredths of a second -1 - Duration of the last wait was less than a hundredth of a second -2 - Parameter TIMED_STATISTICS was set to false This column has been deprecated in favor of the columns WAIT_TIME_MICRO and STATE.
SECONDS_IN_WAIT	NUMBER	If the session is currently waiting, then the value is the amount of time waited for the current wait. If the session is not in a wait, then the value is the amount of time since the start of the last wait. This column has been deprecated in favor of the columns WAIT_TIME_MICRO and TIME_SINCE_LAST_WAIT_MICRO.
STATE	VARCHAR2(19)	Wait state: WAITING - Session is currently waiting WAITED UNKNOWN TIME - Duration of the last wait is unknown; this is the value when the parameter TIMED_STATISTICS is set to false WAITED SHORT TIME - Last wait was less than a hundredth of a second WAITED KNOWN TIME - Duration of the last wait is specified in the WAIT_TIME column
WAIT_TIME_MICRO	NUMBER	Amount of time waited (in microseconds). If the session is currently waiting, then the value is the time spent in the current wait. If the session is currently not in a wait, then the value is the amount of time waited in the last wait.
TIME_REMAINING_MICRO	NUMBER	Value is interpreted as follows: > 0 - Amount of time remaining for the current wait (in microseconds) 0 - Current wait has timed out -1 - Session can indefinitely wait in the current wait NULL - Session is not currently waiting
TIME_SINCE_LAST_WAIT_MICRO	NUMBER	Time elapsed since the end of the last wait (in microseconds). If the session is currently in a wait, then the value is 0.
SERVICE_NAME	VARCHAR2(64)	Service name of the session
SQL_TRACE	VARCHAR2(8)	Indicates whether SQL tracing is enabled (ENABLED) or disabled (DISABLED)
SQL_TRACE_WAITS	VARCHAR2(5)	Indicates whether wait tracing is enabled (TRUE) or not (FALSE)
SQL_TRACE_BINDS	VARCHAR2(5)	Indicates whether bind tracing is enabled (TRUE) or not (FALSE)
SQL_TRACE_PLAN_STATS	VARCHAR2(10)	Frequency at which row source statistics are dumped in the trace files for each cursor: never first_execution all_executions
SESSION_EDITION_ID	NUMBER	Shows the value that, in the session, would be reported by sys_context('USERENV', 'SESSION_EDITION_ID')
CREATOR_ADDR	RAW(4 | 8)	Address of the creating process or circuit
CREATOR_SERIAL#	NUMBER	Serial number of the creating process or circuit
ECID	VARCHAR2(64)	Execution context identifier (sent by Application Server)

^{Footnote 1} The datatype of this column is VARCHAR2(64) starting with Oracle Database 11g Release 2 (11.2.0.2).

^{Footnote 2} The P1RAW, P2RAW, and P3RAW columns display the same values as the P1, P2, and P3 columns, except that the numbers are displayed in hexadecimal.

See Also:

• Oracle Database Performance Tuning Guide for an example of using V$SESSION to determine which sessions are waiting for I/O

• Oracle Database Performance Tuning Guide for an example of using V$SESSION to help identify an object that is waiting for buffer busy waits