Note: This feature only applies to Virtuoso 7.0 and later.
The body of FOR VECTORED or a vectored procedure may contain
arbitrary Virtuoso PL, except for LOOPs and backward GOTOs.
Conditional expressions and statements are allowed, as well as any
subqueries or DML statements. Looping over a cursor is not allowed,
since this is a loop, but scalar subqueries and
selecting-into-variables in SELECT ...
INTO is allowed. Exception handlers are not allowed
inside, but an exception handler outside of FOR VECTORED will catch
errors signaled from inside FOR VECTORED. FOR VECTORED statements
may not be nested and may not occur in the body of a vectored
procedure. The handler, being itself not in vectored code, will not
be able to see which specific value in a vectored section gave rise
to the exception.