The DATE function returns a date from a value. The argument must be a date, timestamp, a positive number less than or equal to 3,652,059, a valid string representation of a date or timestamp, or a string of length 7 that is not a CLOB or LONG VARCHAR. If the argument is a string of length 7, it must represent a valid date in the form yyyynnn, where yyyy are digits denoting a year, and nnn are digits between 001 and 366, denoting a day of that year. The result of the function is a date. If the argument can be null, the result can be null; if the argument is null, the result is the null value.

The
other rules depend on the data type of the argument specified:

- If the argument is a date, timestamp, or valid string representation of a date or timestamp: The result is the date part of the value.
- If the argument is a number: The result is the date that is n-1 days after January 1, 0001, where n is the integral part of the number.
- If the argument is a string with a length of 7: The result is the date represented by the string.

DATE (expression)

This example results in an internal representation of '1988-12-25'.

VALUES DATE('1988-12-25')