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Version: Beta 🚧


Private Preview

This feature is currently in Private Preview.

This feature has the following limitations:
  • Must be enabled by Tecton Support.
If you would like to participate in the preview, please file a feature request.


This class describes a LifetimeWindow that is applied in an Aggregation within a Batch or Stream Feature View.

Lifetime Windows are useful for expressing a feature like "user transaction average since Jan 1, 2000."

For an overview of Aggregation Windows, check out Aggregation Windows.


Tecton Aggregations are applied over a specified time window using the time_window parameter. Use LifetimeWindow to create an Aggregation over a window that continuously expands.

from tecton import batch_feature_view, FilteredSource, Aggregation, TimeWindow

lifetime_start_time=datetime(2000, 1, 1),
aggregations=[Aggregation(column="amount", function="mean", time_window=LifetimeWindow())],
def user_average_transaction_amount(transactions):
return f"""
SELECT user_id, timestamp, amount
FROM {transactions}

The start time of this window is Jan 1, 2000 (as specified by lifetime_start_time). The end time of this window will be the most recent aggregation interval as of an incoming online feature request or training event timestamp (during offline feature retrieval).

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