Details on available Virtual Columns and Virtual Tables

[unknown-user]

Is there any documentation on what Virtual Columns and Virtual Tables Alfresco makes available via CMIS?
Is it possible to configure this?  Is there any documentation?
I can see on the Wiki that sometimes the "cm:" prefix is used (e.g. "cm:thumbnail") but can't find any documentation on it.

I would like to be able to return specific columns (e.g. "title") and select on specific types (e.g. "store") but simply can't find any documentation on what is possible or how to configure it.

TIA.

[unknown-user]

OK, I now know I need to create a "custom model".  I have done enough to prove that this can be done, even though I never got it to work (I simply don't know enough about Alfresco).  But it at least shows me there is a means to manipulate and configure CMIS.