Oracle 参数 NLS_TIMESTAMP_TZ_FORMAT 官方解释，作用，如何配置最优化建议
本站中文解释
:
NLS_TIMESTAMP_TZ_FORMAT参数控制显示TIMESTAMPTZ和TIMESTAMP WITH TIME ZONE类型字段值的格式。
该参数使用比特序列来设置格式。以下是设置比特序列的一些示例:
1.YYYY-MM-DD HH24:MI:SSXFF：这将显示年月日、小时、分钟、秒和时区偏移量;
2.DD-MON-YYYY HH24:MI:SSXFF：将显示日月年、小时、分钟、秒和时区偏移量;
3.HH24:MI:SSXFF：将显示小时、分钟、秒和时区偏移量。
正确设置NLS_TIMESTAMP_TZ_FORMAT参数的方法是：
1.通过ALTER SYSTEM语句动态设置参数：alter system set nls_timestamp_tz_format = ‘YYYY-MM-DD HH24:MI:SSXFF’;
2.如果需要在包括参数在内停机时也有效，那么还需要编辑ORACLE数据库的参数文件，将参数值加入到文件中。
官方英文解释
NLS_TIMESTAMP_TZ_FORMAT defines the default timestamp with time zone format to use with the TO_CHAR and TO_TIMESTAMP_TZ functions.
| Property | Description |
|---|---|
|
Parameter type |
String |
|
Syntax |
|
|
Default value |
Derived from |
|
Modifiable |
|
|
Modifiable in a PDB |
Yes |
|
Range of values |
Any valid datetime format mask |
|
Basic |
No |
The value must be surrounded by quotation marks as follows:
NLS_TIMESTAMP_TZ_FORMAT = 'YYYY-MM-DD HH:MI:SS.FF TZH:TZM'
You can specify the value of NLS_TIMESTAMP_TZ_FORMAT by setting it in the initialization parameter file. You can specify its value for a client as a client environment variable.
You can also alter the value of NLS_TIMESTAMP_TZ_FORMAT by changing its value in the initialization parameter and then restarting the instance. To alter the value during a session use the ALTER SESSION SET statement.
Note:
The value of this initialization parameter NLS_TIMESTAMP_TZ_FORMAT is used to initialize the session value of this parameter, which is the actual value referenced by the SQL query processing. This initial value is overridden by a client-side value if the client uses the Oracle JDBC driver or if the client is OCI-based and the NLS_LANG client setting (environment variable) is defined. The initialization parameter value is, therefore, usually ignored.
See Also:
Oracle Database
Globalization Support Guide for more information about this parameter
