TUMBLING_EXTERNAL_TIME()

A batch (tumbling) time window based on external time, that holds events arrived during window.time periods, and gets updated for every window.time.

Syntax

WINDOW TUMBLING_EXTERNAL_TIME(<LONG> timestamp, <INT|LONG|TIME> window.time)
WINDOW TUMBLING_EXTERNAL_TIME(<LONG> timestamp, <INT|LONG|TIME> window.time, <INT|LONG|TIME> start)
WINDOW TUMBLING_EXTERNAL_TIME(<LONG> timestamp, <INT|LONG|TIME> window.time, <INT|LONG|TIME> start, <INT|LONG|TIME> timeout)
WINDOW TUMBLING_EXTERNAL_TIME(<LONG> timestamp, <INT|LONG|TIME> window.time, <INT|LONG|TIME> start, <INT|LONG|TIME> timeout, <BOOL> replace.with.batchtime)

Query Parameters

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
timestamp	The Unix timestamp in milliseconds which the window determines as current time and will act upon. The value of this parameter should be monotonically increasing. Max. int is 2^32, or 2147483647.		LONG	No	Yes
window.time	The batch time period for which the window should hold events.		INT LONG TIME	No	No
start	User defined start time. This could either be a constant (of type int, long, or time) or an attribute of the corresponding stream (of type long). If an attribute is provided, initial value of attribute would be considered as startTime.	Timestamp of first event	INT LONG TIME	Yes	Yes
timeout	Time to wait for arrival of new event, before flushing and giving output for events belonging to a specific batch.	System waits till an event from next batch arrives to flush current batch	INT LONG TIME	Yes	No
replace.with.batchtime	This indicates to replace the expired event timeStamp as the batch end timeStamp	System waits till an event from next batch arrives to flush current batch	BOOL	Yes	No

Example 1

CREATE STREAM cseEventStream (symbol string, price float, volume int, eventTime long);
CREATE SINK OutputStream WITH (type='stream', stream='OutputStream') (symbol string, price double);
CREATE WINDOW cseEventWindow (symbol string, price float, volume int, eventTime long) TUMBLING_EXTERNAL_TIME(eventTime, 1 sec) OUTPUT expired events;

@info(name = 'query0')
INSERT INTO cseEventWindow
FROM cseEventStream;

@info(name = 'query1')
INSERT expired events INTO OutputStream 
SELECT symbol, sum(price) AS price
FROM cseEventWindow;

This processes events that arrive every second from the eventTime.

Example 2

CREATE STREAM cseEventStream (symbol string, price float, volume int, eventTime long);
CREATE WINDOW cseEventWindow (symbol string, price float, volume int, eventTime long) TUMBLING_EXTERNAL_TIME(eventTime, 20 sec, 0) OUTPUT expired events;

This processes events that arrive every 1 seconds from the eventTime. Starts on 0th millisecond of an hour.

Example 3

CREATE STREAM cseEventStream (symbol string, price float, volume int, eventTime long, eventTimestamp long);
CREATE WINDOW cseEventWindow (symbol string, price float, volume int, eventTime long, eventTimestamp long) TUMBLING_EXTERNAL_TIME(eventTime, 2 sec, eventTimestamp, 100) OUTPUT expired events;

This processes events that arrive every two seconds from the eventTime. Considers the first event's eventTimestamp value as startTime. Waits 100 milliseconds for the arrival of a new event before flushing current batch.