SQL Backend for IMAP METADATA Dictionary

[Joseph D Wagner]

I've seen documentation on using a SQL backend for quota dictionary and
passdb&userdb dictionary. However, I can't find any examples of a SQL
backend for IMAP METADATA / mail_attributes_dict.

Is this combination possible?  If so, is there an example somewhere?

I am unsure what data structures it's expected or how to create the map
entries for it.

Thanks in advance.

Joseph D. Wagner