Oracle Database includes a bunch of NLS (National Language Support) parameters that determine the locale-specific behaviour on both the client and the server.
These NLS parameters can be set in various places, each of which has a predetermined precedence order in relation to the others. The following table outlines these methods, as well as their priority in relation to the others.
In Oracle Database, the NLS_LANGUAGE initialization parameter specifies the default language of the database.
This language is used for messages, day and month names, symbols for AD, BC, a.m., and p.m., and the default sorting mechanism.
The NLS_LANGUAGE parameter also determines the default values of the NLS_DATE_LANGUAGE and NLS_SORT parameters.
This article outlines how to change the value of the NLS_LANGUAGE and NLS_DATE_LANGUAGE parameters.
In Oracle Database, the CURRENT_DATE function returns the current date in the session time zone, in a value in the Gregorian calendar of data type DATE.
When using Oracle Database, you can find out what languages are supported by querying the V$NLS_VALID_VALUES view.
This view lists all valid values for NLS parameters, including supported languages.
When using Oracle Database, you can find out what territories are supported by querying the V$NLS_VALID_VALUES view.
This view lists all valid values for NLS parameters, including supported territories.
In Oracle Database, the CURRENT_TIMESTAMP() function returns the current date and time in the session time zone, in a value of data type TIMESTAMP WITH TIME ZONE.
It’s similar to LOCALTIMESTAMP, except that LOCALTIMESTAMP returns a TIMESTAMP value.
In Oracle Database, the LOCALTIMESTAMP() function returns the current date and time in the session time zone in a value of data type TIMESTAMP.
It’s similar to CURRENT_TIMESTAMP, except that CURRENT_TIMESTAMP returns a TIMESTAMP WITH TIME ZONE value.
In Oracle Database, the SYSTIMESTAMP function returns the system date, including fractional seconds and time zone, of the system on which the database resides.
The returned value is of type TIMESTAMP WITH TIME ZONE.
In Oracle Database, the SYSDATE function returns the current date and time set for the operating system on which the database server resides.
The returned value is of type DATE.
In Oracle Database, the EXTRACT(datetime) function extracts and returns the value of a specified datetime field from a datetime or interval expression.