If you look at the
link provided above you'll see that we did settle on the p_* and v_* notation. I guess that never got migrated to our docs.
The problem we face (as always) is legacy code, there are lots of queries out there using named parameters ("param_name => value") in calls to PL/SQL and breaking them is something we were loath to do, given that we knew some folks would be migrated aD 4.2 sites to OpenACS 4 etc.
For new stuff though I'd love to see us settle on that convention if others agree. Do we have something like consensus among those posting to this thread? If so, let's TIP it.