1. What is the ES
** ** ES stands ** ElasticSearch ** is a distributed full-text search engine based on Lucene (full-text search framework) developed from.
Lucene is recognized as the best use of search engine library to date, but he provides API for our users, it is very distressing, often have to spend a lot of time to get familiar with the study. ES appears a good solution to this problem, a good package, easy to use API, writing style chain, opened bottles of drinks.
2.ES Features
** ES ** albeit Lucene core library development, but it is not as the core, ** ES ** posted point is reflected in:
* Real-time distributed file storage, each field have encountered index *
* clustering, scalability (theoretically unlimited) *
* highly integrated services (RESTful style API, each client language) *
* easy to use, open a bottle of the drink *
ES document CRUD
relational database (MYSQL) -> Database DB-> Table TABLE-> row ROW-> Column Column
elasticsearch -> index Library Indices -> type Types -> Documents Documents -> Fields Fields
ES cluster can contain multiple indexes (indices) (database), each of the index database may contain a plurality of types (types) (table), each type including a plurality of documents (documents) (OK), then each document comprising a plurality of fields (fields) ( column).
Initially, we talked about the "Index" similar to the SQL database "database" and "type" is equivalent to "watch."
This is a bad analogy, leads to wrong assumptions. In SQL databases, tables independent of each other. Regardless of columns in a table of columns and another table with the same name. Mapping type of field is not the case.