不爲也 比不能也

Lucene 6.0 introduced new exciting feature called multi-dimensional points. While the name of the feature puts a lot of emphasis on the fact that it supports multiple dimensions, this feature behaves more than decently in the case of a single dimension and actually better than the trie encoding that was used in previous versions of Lucene. This caused us to refactor number-based fields (byte, sh..

UPDATE: This article refers to our hosted Elasticsearch offering by an older name, Found. Please note that Found is now known as Elastic Cloud.이 게시물은 기존에 Found라는 이름으로 제공된 Elasticsearch 서비스에 관한 것이다. Found은 이제 Elasticsearch Cloud로 알려져 있다.In this article series, we look at Elasticsearch from a new perspective. We'll start at the "bottom" (or close enough!) of the many abstraction levels, and gradua..

Elasticsearch is an open-source search engine built on top of Apache Lucene™, a full-text search-engine library. Lucene is arguably the most advanced, high-performance, and fully featured search engine library in existence today—both open source and proprietary.Elasticsearch는 Apache Lucene™을 기반으로 만들어진 검색 엔진이며, full-text 검색 엔진 라이브러리이다. Lucene은, Open Source와 상업용 양쪽 모두를 살펴보더라도, 오늘날 현존하는 가장 고급스러운, 고..

To add data to Elasticsearch, we need an index—a place to store related data. In reality, an index is just a logical namespace that points to one or more physical shards.Elasticsearch에 데이터를 추가하기 위해서는, 관련된 데이터를 저장할 수 있는 장소인 index 가 필요하다.실제로, index는 하나 이상의 물리적인 shards 를 가리키는 logical namespace 이다.A shard is a low-level worker unit that holds just a slice of all the data in the index. In Inside a Sh..

Lucene (and thus Elasticsearch) uses the Boolean model to find matching documents, and a formula called the practical scoring function to calculate relevance. This formula borrows concepts from term frequency/inverse document frequency and the vector space model but adds more-modern features like a coordination factor, field length normalization, and term or query clause boosting.Lucene과 Elastic..

For multiterm queries, Lucene takes the Boolean model, TF/IDF, and the vector space model and combines them in a single efficient package that collects matching documents and scores them as it goes.다중 단어 query의 경우, Lucene은 Boolean model, TF/IDF 그리고, vector space model을 가지고, 일치하는 document를 수집하고, score를 계산하는, 하나의 효율적인 패키지로 그들을 조합한다.A multiterm query like다중 단어 query는GET /my_index/doc/_search { "que..