TRUNC function - Amazon Redshift
SyntaxArgumentsReturn TypeExamples
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TRUNC function

Truncates a TIMESTAMP and returns a DATE.

This function can also truncate a number. For more information, see TRUNC function.

Syntax

TRUNC(timestamp)

Arguments

timestamp

A column of data type TIMESTAMP or an expression that implicitly evaluates to a TIMESTAMP type.

To return a timestamp value with 00:00:00 as the time, cast the function result to a TIMESTAMP.

Return type

DATE

Examples

The following example returns the date portion from the result of the SYSDATE function (which returns a timestamp). 

SELECT SYSDATE;

+----------------------------+
|         timestamp          |
+----------------------------+
| 2011-07-21 10:32:38.248109 |
+----------------------------+

SELECT TRUNC(SYSDATE);

+------------+
|   trunc    |
+------------+
| 2011-07-21 |
+------------+

The following example applies the TRUNC function to a TIMESTAMP column. The return type is a date. 

SELECT TRUNC(starttime) FROM event
ORDER BY eventid LIMIT 1;

+------------+
|   trunc    |
+------------+
| 2008-01-25 |
+------------+

The following example returns a timestamp value with 00:00:00 as the time by casting the TRUNC function result to a TIMESTAMP.

SELECT CAST((TRUNC(SYSDATE)) AS TIMESTAMP);

+---------------------+
|        trunc        |
+---------------------+
| 2011-07-21 00:00:00 |
+---------------------+