The
DATE function returns a date from a value.
>>-DATE--(--expression--)--------------------------------------><
- expression
- An expression that returns a value of one of the following built-in
data types: DATE, TIMESTAMP, numeric, or character string that is
not a CLOB.
A value with a numeric data type must be a positive
number with an integral value less than or equal to 3 652 059.
A
character string must be a valid string representation of a date or
timestamp or a string of length 7. If the value 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.
In
a Unicode database, if an expression returns a value of a graphic
string data type, the value is first converted to a character string
before the function is executed.
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:
- 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.
Examples
Assume that the column RECEIVED
(whose data type is TIMESTAMP) has an internal value equivalent to
'1988-12-25-17.12.30.000000'.
- Example 1: This example results in an internal representation
of '1988-12-25'.
DATE(RECEIVED)
- Example 2: This example results in an internal representation
of '1988-12-25'.
DATE('1988-12-25')
- Example 3: This example results in an internal representation
of '1988-12-25'.
DATE('25.12.1988')
- Example 4: This example results in an internal representation
of '0001-02-04'.
DATE(35)
DB2 10.5 for Linux, UNIX, and Windows