ALTER SESSION v11
Name
ALTER SESSION
-- change a runtime parameter.
Synopsis
Description
The ALTER SESSION
command changes runtime configuration parameters. ALTER SESSION
only affects the value used by the current session. Some of these parameters are provided solely for compatibility with Oracle syntax and have no effect whatsoever on the runtime behavior of Advanced Server. Others will alter a corresponding Advanced Server database server runtime configuration parameter.
Parameters
name
Name of a settable runtime parameter. Available parameters are listed below.
value
New value of parameter.
Configuration Parameters
The following configuration parameters can be modified using the ALTER SESSION
command:
NLS_DATE_FORMAT (string)
Sets the display format for date and time values as well as the rules for interpreting ambiguous date input values. Has the same effect as setting the Advanced Server
datestyle
runtime configuration parameter.NLS_LANGUAGE (string)
Sets the language in which messages are displayed. Has the same effect as setting the Advanced Server
lc_messages
runtime configuration parameter.NLS_LENGTH_SEMANTICS (string)
Valid values are
BYTE
andCHAR
. The default isBYTE
. This parameter is provided for syntax compatibility only and has no effect in the Advanced Server.OPTIMIZER_MODE (string)
Sets the default optimization mode for queries. Valid values are
ALL_ROWS
,CHOOSE
,FIRST_ROWS
,FIRST_ROWS_10
,FIRST_ROWS_100
, andFIRST_ROWS_1000
. The default isCHOOSE
. This parameter is implemented in Advanced Server.QUERY_REWRITE_ENABLED (string)
Valid values are
TRUE
,FALSE
, andFORCE
. The default isFALSE
. This parameter is provided for syntax compatibility only and has no effect in Advanced Server.QUERY_REWRITE_INTEGRITY (string)
Valid values are
ENFORCED
,TRUSTED
, andSTALE_TOLERATED
. The default isENFORCED
. This parameter is provided for syntax compatibility only and has no effect in Advanced Server.
Examples
Set the language to U.S. English in UTF-8 encoding. Note that in this example, the value, en_US.UTF-8
, is in the format that must be specified for Advanced Server. This form is not compatible with Oracle databases.
Set the date display format.