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If a grace period is not set the join will execute as before, using the same logic in the stream table join node. If a grace period of zero is set the join will execute as a normal join as each record comes it will try to join to the point of time in the versioned table. If the grace period is non zero, the record will enter a stream buffer and will dequeue when the record timestamp is lees than or equal to than stream time plus minus the grace period.  Late records, out of the grace period, will be executed right as they come in.

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