Hmm. I would think that you wouldn't want to open a new psql connection every time you want to look something up.
How about running the system command in a thread, which redirects psql's stdin and stdout to named pipes so that another arc thread could read from it using file read commands? That would give you more persistence, so you wouldn't have to keep loading psql.
Also, have a look at lib/mysql-ffi.arc in anarki; supposedly it has a ffi for mysql, though I haven't really looked at it much myself.
