I see the other comment is marked dead now, but seriously why? I'm having a hard time imagining how a schema is viewed as actual intellectual property or a security risk.

Intellectual property: it represents what kinds of data you maintain, their naming, and their relation. That’s valuable on its own and also points to what your software does.

Security: well, see above—knowing what data is stored determines your value as a target.

Now is it the _best_ way to target an adversary? Probably not.

Show me your flowchart and conceal your tables, and I shall continue to be mystified. Show me your tables, and I won't usually need your flowchart; it'll be obvious." -- Fred Brooks, The Mythical Man Month (1975)