I’m storing data using the db4o persistence service, all seems to work fine.
For some calculations, I need to know when the first occurrence of an item was stored.
I found this list of extensions : http://tinyurl.com/gr7mosh but I’m looking for something like:
<>.firstUpdate - Query for the first update timestamp of a given item…
How difficult is it to make such an extension or are there better/easier ways of doing this ?