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TUMBLING_TIME_LENGTH

This is a batch or tumbling time length window that is updated with the latest events based on a unique key parameter. The window tumbles upon the elapse of the time window, or when a number of unique events have arrived. If a new event that arrives within the period of the window has a value for the key parameter which matches the value of an existing event, the existing event expires and it is replaced by the new event.

Syntax

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

Query Parameters

NameDescriptionDefault ValuePossible Data TypesOptionalDynamic
unique.keyThe attribute that should be checked for uniqueness.INT LONG FLOAT BOOL DOUBLE STRINGNoYes
window.timeThe sliding time period for which the window should hold the events.INT LONGNoNo
start.timeThis specifies an offset in milliseconds in order to start the window at a time different to the standard time.Timestamp of first eventINT LONGYesNo
window.lengthThe number of events the window should tumble.INTNoNo

Example 1

    CREATE STREAM CseEventStream (symbol string, price float, volume int)

INSERT all events INTO OutputStream
SELECT symbol, price, volume
FROM CseEventStream WINDOW UNIQUE:TUMBLING_TIME_LENGTH(symbol, 1 sec, 20);

This window holds the latest unique events that arrive from the CseEventStream at a given time, and returns all the events to the OutputStream. It is updated every second based on the latest values for the symbol attribute.