Q on JDBC's resultset

Hello.

I looked in the source and have the feeling that if I
execute a SELECT statement, the whole resultset comes through
the network in one large bundle.

Is it true?

It means that I cannot enable to use simple tablemodel and
table on top of an sql query, since it would be too slow to
download all of the data when opening it.

Anyway, how does the backend handles this? If I execute a query,
it copies the result immediately to a separate place?? So for
a SELECT *... query on a 2GB table results immediately in the
occupance of an pther two gigs?

Lastly, does anyone plans to work on updatable cursors? I think
that would make possibel to create read/write tablemodels in
Java.

Thanks,
Baldvin

p.s.: Does anyone knows if mysql supports updatable queries and
complete jdbc?