What is Elasticsearch:
Elasticsearch, distributed, high-performance, highly available, scalable search and analysis system
1. What is a search?
Search is under any scenario, to find the information you want, at this time, you can enter a keyword to search for a while, and then expect to find some information related to this keyword
Electricity supplier sites, job sites, news sites, various app,: Baidu, vertical search (station search), the Internet search search IT systems: OA software, office automation software, conference management, schedule management, project management, staff management , search for "John Doe", "Joe Smith children", "Zhang three"; there is electricity's website, the seller, back office systems, search for "toothpaste" orders, "toothpaste-related orders."
2. What happens if you do a search with a database?
Do software development, then, or for IT, computers have a certain understanding, then, to know that the data is stored in a database, for example product information electricity supplier site, jobs recruitment site, news site news and information, etc. wait. So, it is natural that, if to consider from a technical point of view, such as how to say, the internal electricity supplier site search, then you can consider, to use the database to search.
1, designated text fields for each record, may be very long, for example, the length of the "product description" field, as long as there are thousands, even tens of thousands of characters, this time, every time for each record All text is scanned to determine that your package does not contain the key words I specify (such as "toothpaste")
2, can not yet search terms split open, as far as possible to search more in line with your expectations the result of
Search the database to achieve, it is unlikely to fly. In general, the performance will be poor.
3. What is the full-text search and Lucene?
(1) full-text search inverted index
(2) lucene, is a jar package, which contains a variety of packaged create an inverted index, and search code, including various algorithms. When we use java development, the introduction of lucene jar, then based api lucene were to develop it. With lucene, we can go to the existing data indexing, lucene local disk above will give us the organizational structure of the index data. In addition, we can use some of the features and api lucene to provide for the amount of disk
4. What is Elasticsearch?
