Xindice (pronounced "zeen-dee-chay") is an open source native XML database from the Apache Software Foundation.
You might be wondering what a native XML database is good for? Well it pretty much has one purpose, storing XML data. ... The benefit of a native solution is that you don't have to worry about mapping your XML to some other data structure. You just insert the data as XML and retrieve it as XML. ... This is especially valuable when you have very complex XML structures that would be difficult or impossible to map to a more structured database. ... At the present time Xindice uses XPath for its query language and XML:DB XUpdate for its update language.
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