firstWriteWins and lastWriteWins

firstWriteWins always takes the first value seen at the annotated location. Likewise, lastWriteWins always takes the last. Schemas that don’t have an explicit reduce annotation default to lastWriteWins behavior.

collections:
  - name: example/reductions/fww-lww
    schema:
      type: object
      reduce: { strategy: merge }
      properties:
        key: { type: string }
        fww: { reduce: { strategy: firstWriteWins } }
        lww: { reduce: { strategy: lastWriteWins } }
      required: [key]
    key: [/key]

tests:
  "Expect we can track first- and list-written values":
    - ingest:
        collection: example/reductions/fww-lww
        documents:
          - { key: "key", fww: "one", lww: "one" }
          - { key: "key", fww: "two", lww: "two" }
    - verify:
        collection: example/reductions/fww-lww
        documents:
          - { key: "key", fww: "one", lww: "two" }