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Please keep the discussion on the mailing list rather than commenting on the wiki (wiki discussions get unwieldy fast).
Motivation
Unlike for key-value state stores, Kafka Streams currently does not provide a way to query the range of keys available in a windowed state store.
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Similarly, session stores currently only offer querying by a single given key, requiring the user to maintain the set of queryable keys separately.
Public Interfaces
This KIP would add the following methods:
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