extract (Function)

Function extracts a date unit from the date.

Syntax

<INT> time:extract(<STRING> unit, <STRING> date.value)
<INT> time:extract(<STRING> unit, <STRING> date.value, <STRING> date.format)
<INT> time:extract(<STRING> unit, <STRING> date.value, <STRING> date.format, <STRING> locale)
<INT> time:extract(<LONG> timestamp.in.milliseconds, <STRING> unit)
<INT> time:extract(<LONG> timestamp.in.milliseconds, <STRING> unit, <STRING> locale)

Query Parameters

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
unit	This is the part of the date that needs to be modified. For example, MINUTE, HOUR, MONTH, YEAR, QUARTER, WEEK, DAY, SECOND.		STRING	No	No
date.value	The value of the date. For example, 2014-11-11 13:23:44.657, 2014-11-11, 13:23:44.657.	-	STRING	Yes	Yes
date.format	The format of the date value provided. For example, yyyy-MM-dd HH:mm:ss.SSS.	yyyy-MM-dd HH:mm:ss.SSS	STRING	Yes	Yes
timestamp.in.milliseconds	The date value in milliseconds. For example, 1415712224000L.	-	LONG	Yes	Yes
locale	Represents a specific geographical, political or cultural region. For example en_US and fr_FR	Current default locale set in the Java Virtual Machine.	STRING	Yes	No

Example 1

SELECT time:extract('YEAR', '2019/11/11 13:23:44.657', 'yyyy/MM/dd HH:mm:ss.SSS') AS year;

This query extracts the year from the given timestamp string '2019/11/11 13:23:44.657' in the format 'yyyy/MM/dd HH:mm:ss.SSS'. The output is '2019'.

Example 2

SELECT time:extract('DAY', '2019-11-12 13:23:44.657') AS day;

This query extracts the day from the given timestamp string '2019-11-12 13:23:44.657'. The output is '12'.

Example 3

SELECT time:extract('HOUR', 1394556804000L) AS hour;

This query extracts the hour from the given timestamp in milliseconds 1394556804000L. The output is '22'.

Example 4

CREATE STREAM InputStream (timestampStr string, format string);
CREATE SINK STREAM OutputStream (extractedValue int);

@info(name = 'dayExtractorQuery')
INSERT INTO OutputStream
SELECT time:extract('DAY', timestampStr, format) AS extractedValue
FROM InputStream;

The dayExtractorQuery processes events from the InputStream, which contains a timestamp string (timestampStr) and its corresponding format (format). It uses the time:extract('DAY', timestampStr, format) function to extract the day from the timestamp string in the specified format. The query outputs the extracted day as the extractedValue attribute for each event to the OutputStream.