Monday, August 11, 2008

V$PARAMETER2

Oracle 11gR1

V$PARAMETER2 displays information about the initialization parameters that are currently in effect for the session, with each list parameter value appearing as a row in the view. A new session inherits parameter values from the instance-wide values displayed in the V$SYSTEM_PARAMETER2 view.

Presenting the list parameter values in this format enables you to quickly determine the values for a list parameter. For example, if a parameter value is a, b, then the V$PARAMETER view does not tell you if the parameter has two values (both a and b) or one value (a, b). V$PARAMETER2 makes the distinction between the list parameter values clear.

Column

Datatype

Description

NUM

NUMBER

Parameter number

NAME

VARCHAR2(80)

Name of the parameter

TYPE

NUMBER

Parameter type:

· 1 - Boolean

· 2 - String

· 3 - Integer

· 4 - Parameter file

· 5 - Reserved

· 6 - Big integer

VALUE

VARCHAR2(4000)

Parameter value for the session (if modified within the session); otherwise, the instance-wide parameter value

DISPLAY_VALUE

VARCHAR2(4000)

Parameter value in a user-friendly format. For example, if the VALUE column shows the value 262144 for a big integer parameter, then the DISPLAY_VALUE column will show the value 256K.

ISDEFAULT

VARCHAR2(6)

Indicates whether the parameter is set to the default value (TRUE) or the parameter value was specified in the parameter file (FALSE)

ISSES_MODIFIABLE

VARCHAR2(5)

Indicates whether the parameter can be changed with ALTER SESSION (TRUE) or not (FALSE)

ISSYS_MODIFIABLE

VARCHAR2(9)

Indicates whether the parameter can be changed with ALTER SYSTEM and when the change takes effect:

· IMMEDIATE - Parameter can be changed with ALTER SYSTEM regardless of the type of parameter file used to start the instance. The change takes effect immediately.

· DEFERRED - Parameter can be changed with ALTER SYSTEM regardless of the type of parameter file used to start the instance. The change takes effect in subsequent sessions.

· FALSE - Parameter cannot be changed with ALTER SYSTEM unless a server parameter file was used to start the instance. The change takes effect in subsequent instances.

ISINSTANCE_MODIFIABLE

VARCHAR2(5)

For parameters that can be changed with ALTER SYSTEm, indicates whether the value of the parameter can be different for every instance (TRUE) or whether the parameter must have the same value for all Real Application Clusters instances (FALSE). If the ISSYS_MODIFIABLE column is FALSE, then this column is always FALSE.

ISMODIFIED

VARCHAR2(10)

Indicates whether the parameter has been modified after instance startup:

· MODIFIED - Parameter has been modified with ALTER SESSION

· SYSTEM_MOD - Parameter has been modified with ALTER SYSTEM (which causes all the currently logged in sessions' values to be modified)

· FALSE - Parameter has not been modified after instance startup

ISADJUSTED

VARCHAR2(5)

Indicates whether Oracle adjusted the input value to a more suitable value (for example, the parameter value should be prime, but the user input a non-prime number, so Oracle adjusted the value to the next prime number)

ISDEPRECATED

VARCHAR2(5)

Indicates whether the parameter has been deprecated (TRUE) or not (FALSE)

ISBASIC

VARCHAR2(5)

Indicates whether the parameter is a basic parameter (TRUE) or not (FALSE)

DESCRIPTION

VARCHAR2(255)

Description of the parameter

ORDINAL

NUMBER

Position (ordinal number) of the parameter value. Useful only for parameters whose values are lists of strings.

UPDATE_COMMENT

VARCHAR2(255)

Comments associated with the most recent update

Note:

You can view parameter settings in several ways, as shown in the following table.

Method

Description

SHOW PARAMETERS

This SQL*Plus command displays the values of initialization parameters in effect for the current session.

SHOW SPPARAMETERS

This SQL*Plus command displays the values of initialization parameters in the server parameter file (SPFILE).

CREATE PFILE

This SQL statement creates a text initialization parameter file (PFILE) from the SPFILE or from the current in-memory settings. You can then view the PFILE with any text editor.

V$PARAMETER

This view displays the values of initialization parameters in effect for the current session.

V$PARAMETER2

This view displays the values of initialization parameters in effect for the current session. It is easier to distinguish list parameter values in this view because each list parameter value appears in a separate row.

V$SYSTEM_PARAMETER

This view displays the values of initialization parameters in effect for the instance. A new session inherits parameter values from the instance-wide values.

V$SYSTEM_PARAMETER2

This view displays the values of initialization parameters in effect for the instance. A new session inherits parameter values from the instance-wide values. It is easier to distinguish list parameter values in this view because each list parameter value appears in a separate row.

V$SPPARAMETER

This view displays the current contents of the SPFILE. The view returns FALSE values in the ISSPECIFIED column if an SPFILE is not being used by the instance.

Oracle dynamic performance views

No comments:

Post a Comment