TUMBLING_LENGTH

This is a batch (tumbling) window that holds a specified number of latest unique events. The unique events are determined based on the value for a specified unique key parameter. The window is updated for every window length, i.e., for the last set of events of the specified number in a tumbling manner. When a new event arrives within the window length having the same value for the unique key parameter as an existing event in the window, the previous event is replaced by the new event.

Syntax

    WINDOW UNIQUE:TUMBLING_LENGTH(<INT|LONG|FLOAT|BOOL|DOUBLE|STRING> unique.key, <INT> window.length)

Query Parameters

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
unique.key	The attribute that should be checked for uniqueness.		INT LONG FLOAT BOOL DOUBLE STRING	No	Yes
window.length	The number of events the window should tumble.		INT	No	No

Example 1

    CREATE WINDOW CseEventWindow (symbol string, price float, volume int);

    INSERT expired events INTO OutputStream
    SELECT symbol, price, volume
    FROM CseEventStream WINDOW UNIQUE:TUMBLING_LENGTH(symbol, 10);

In this query, the window at any give time holds the last 10 unique events from the CseEventStream stream. Each of the 10 events within the window at a given time has a unique value for the symbol attribute. If a new event has the same value for the symbol attribute as an existing event within the window length, the existing event expires and it is replaced by the new event. The query returns expired individual events as well as expired batches of events to the OutputStream stream.