In addition of what Sylvain said, You can close the table after You use it (if you do that in procedure, functions):
FUNCTION WhatEver()
LOCAL is_sub_not_open
IF .NOT. USED ("Sub")
USE Sub IN 0
is_sub_not_open = .t.
ENDIF
SELECT Sub
...
IF is_sub_not_open
USE IN Sub
ENDIF
...
RETURN
Against Stupidity the Gods themselves Contend in Vain - Johann Christoph Friedrich von Schiller
The only thing normal about database guys is their tables.
