The last section opened by saying doc values are "fast, efficient and memory-friendly". Those are some nice marketing buzzwords, but how do doc values actually work?지난 장에서 doc value는 "빠르고, 효율적이며, 메모리 친화적" 이라고 언급했었다. 약간은 멋진 마케팅 전문용어이긴 하지만, 실제로 doc values는 어떻게 동작할까?Doc values are generated at index-time, alongside the creation of the inverted index. That means doc values are generated on a per-seg..