> AFAIK, there is no need to call unprepare and close.

There is if you want the resources on the server allocated to that statement
to be released.
Otherwise, that won't happen until the connection is disconnected or the
object instance is destroyed.

My rule of thumb is, if you aren't going to use a statement again in its
prepared state then Unprepare it.
Keep something prepared for an on-going process or something that you want
primed and ready to go.

HTH,
Jason Wharton
CPS - Mesa AZ
http://www.ibobjects.com