DataGuide is a "structural summary" for semistructured data and may be considered as analog of traditional database schema in context of semistructured data management.

DataGuide is a descriptive schema for XML/SXML data. While prescriptive schemas (DTD, XML Schema, Relax-NG) act more as a traditional datanase schema, restricting allowable XML data, a DataGuide infers rather than imposes structure.

DataGuide describes actual (rather than possible) structure of XML data extracting the structure from the XML data. It may be used as schema for semistructered data without any explicit schema declaration, such as non-validated XML documents.

Strong DataGuide for a SXML tree s is a SXML tree dg such that exactly one element or attribute exists in dg for every location path of s, and every location path of dg is a location path of s.

Flat DataGuide for a SXML tree s is a list of location paths dg such that exactly one location path exists in dg for every location path of s, and every location path in dg is a location path of s.

Software

guides.ss
is included in SXML collection for PLT Schemes

dg.scm
A command line tool for DataGuides extraction and comparison. Requires "ssax" and "sxml" collections available from the link above.