Question

Search engines are NoSQL database management systems dedicated to the search for data content. In addition to general optimization for this type of application, the specialization consists in typically offering the following features:

• Support for complex search expressions 支持复杂搜索表达式
• Full text search 全文搜索
• Stemming (reducing inflected words to their stem) 词干（减少词干变化的词）
• Ranking and grouping of search results 搜索结果评分和分组
• Geospatial search 地理检索
• Distributed search for high scalability 高可用分布式检索

搜索引擎	Description	诞生	语言	特性	Developer	License
Elasticsearch	A modern search and analytics engine based on Apache Lucene	2010	Java		Elastic	Open Source
Splunk	Analytics Platform for Big Data	2003			Splunk Inc.	commercial
Solr	A widely used enterprise search engine based on Apache Lucene	2004	Java		Apache Software Foundation	Open Source
MarkLogic	Operational and transactional Enterprise NoSQL database	2001	C++		MarkLogic Corp.	commercial
Sphinx	Open source search engine for searching in data from different sources, e.g. relational databases	2001	C++		Sphinx Technologies Inc.	Open Source
Microsoft Azure Search						commercial
Algolia
Google Search Appliance						commercial
Amazon CloudSearch						commercial