Hi,
Orbeon Forms doesn't yet support SQL Server out-of-the-box, at least for forms you create in Form Builder, which I assume is what you're interested in. Right now Orbeon Forms supports eXist, Oracle, MySQL, and DB2. You can find those implementation in:
https://github.com/orbeon/orbeon-forms/tree/master/src/resources/apps/fr/persistenceI think the best way to support SQL Server would be to take one of these implementations, "clone it", and adapt the SQL statement as necessary for SQL Server. To do so, I would start from the MySQL or DB2 version (which are very very similar).
Alex
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