[Geary] Geary and its SQL tables

[eric moutie laposte net]

Hello there, 

I've installed Geary on Ubuntu and it works well. I'd like to make a SQL query to archive 
one year for exemple, which would create a stand-alone database. I've looked at the code 
and the SQLite database. Some relationships are evident between:
- [MessageTable][id]<->[MessageAttachmentTable][message_id] 
- [MessageTable][id]<->[MessageLocationTable][message_id] 
- [MessageLocationTable][folder_id]<->[FolderTable][id]. 

However, is there already an ERD diagram showing the relationships between the tables? 
This would facilitate me the writing. 

Cordially.
Eric.