@Override
  public void put(K key, V val, long timestamp) {
    // For append mode, values are differentiated by an unique sequence number. For overwrite mode, the sequence
    // number is always zero. This ensures that only the most recent value is retained.
    if (appendMode) {
      seqNum.getAndIncrement();
    }
    TimeSeriesKey<K> timeSeriesKey = new TimeSeriesKey<>(key, timestamp, seqNum.get());

    LOG.trace("Inserting {} -> {} into the store", timeSeriesKey, val);
    kvStore.put(timeSeriesKey, val);
  }
Creates a {@link TimeSeriesStoreImpl} in append mode.

@param kvStore the backing kv store to use
samza-core/src/main/java/org/apache/samza/operators/impl/store/TimeSeriesStoreImpl.java