SSQML
A schema to describe ANSI/ISO SQL in XML and associated tools
...The schema is based on Backus Normal Form (BNF) representations of ANSI-ISO/IEC SQL Standards; ISO/IEC 9075 :2003, ISO/IEC 9075 :2006, ISO/IEC 9075 :2008, ISO/IEC 9075-14 :2013 XML-Related Specifications (SQL/XML)
Does not include support for Embedded SQL Ada, C, COBOL, Fortran, MUMPS, Pascal, or PL/I programs. These may be added in future.
This schema was generated by automation taking the SQL BNFs as input. It was then run through schema validators and manually modified further to result in a valid schema.
The schema was designed such that if an instance document has its tags removed and the order of the content preserved, a valid SQL statement or fragment will be left.
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