Zebra - Indexing and Retrieval Engine
Zebra is a high-performance, general-purpose structured text indexing and retrieval engine. It can index records in XML/SGML, MARC, e-mail archives and many other formats and allows access to them through exact boolean search expressions and relevance-ranked free-text queries.
Zebra supports large databases (more than ten gigabytes of data, tens of millions of records). It supports incremental database updates. PHP/YAZ tool provides an interface to work with Zebra. Zebra provides API and Web services support. Applications from variety of other programming languages could access Zebra server and perform search and retrieval.