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A window that holds an incoming events batch. When a new set of events arrives, the old events are expired. Tumbling windows can be used to aggregate events that comes in batches. If it has the parameter length specified, then the batch window processes the batch as several chunks.



Query Parameters

NameDescriptionDefault ValuePossible Data TypesOptionalDynamic
lengthThe length of a batch.If length value was not given, it assigns 0 as length and process the whole batch at once.INTYesNo

Example 1

CREATE STREAM consumerItemStream (itemId string, price float);
CREATE SINK STREAM OutputStream (price float, itemIds string);

INSERT INTO OutputStream
SELECT price, str:groupConcat(itemId) AS itemIds
FROM consumerItemStream WINDOW TUMBLING()
GROUP BY price;

This outputs comma-separated item IDs that have the same price for each incoming batch of events.