Functions, 137 of 177

TO_DATE

Syntax

to_date::=

Text description of functions105.gif follows

Purpose

TO_DATE converts char of CHAR, VARCHAR2, NCHAR, or NVARCHAR2 datatype to a value of DATE datatype. The fmt is a date format specifying the format of char. If you omit fmt, then char must be in the default date format. If fmt is 'J', for Julian, then char must be an integer.

Note:

This function does not convert data to any of the other datetime datatypes. For information on other datetime conversions, please refer to TO_TIMESTAMP , TO_TIMESTAMP_TZ , TO_DSINTERVAL , and "TO_YMINTERVAL".

The default date format is determined implicitly by the NLS_TERRITORY initialization parameter, or can be set explicitly by the NLS_DATE_FORMAT parameter.

The 'nlsparam' has the same purpose in this function as in the TO_CHAR function for date conversion.

Do not use the TO_DATE function with a DATE value for the char argument. The first two digits of the returned DATE value can differ from the original char, depending on fmt or the default date format.

Note:

This function does not support CLOB data directly. However, CLOBs can be passed in as arguments through implicit data conversion. Please refer to "Datatype Comparison Rules" for more information.

See Also:

"Date Format Models"

Examples

The following example converts a character string into a date:

SELECT TO_DATE(
    'January 15, 1989, 11:00 A.M.',
    'Month dd, YYYY, HH:MI A.M.',
     'NLS_DATE_LANGUAGE = American')
     FROM DUAL;

TO_DATE('
---------
15-JAN-89

The value returned reflects the default date format if the NLS_TERRITORY parameter is set to 'AMERICA'. Different NLS_TERRITORY values result in different default date formats:

ALTER SESSION SET NLS_TERRITORY = 'KOREAN';

SELECT TO_DATE(
    'January 15, 1989, 11:00 A.M.',
    'Month dd, YYYY, HH:MI A.M.',
     'NLS_DATE_LANGUAGE = American')
     FROM DUAL;

TO_DATE(
--------
89/01/15