Gene,

This sounds right. 

Standard insert as append does freelist block checking
and generates redo. Parallel DML generates minimial
redo, just for the new temp segments being created,
not for the datablock updates. This is one reason it
is so fast.

Index changes are always logged, even in PDML and
append modes.

One way to consider would be to alter indexes to
unusable and rebuild with nologging and compute
statistics clauses. This way, your load is fast, you
generate minimal redo, and your indexes are balanaced
and have good stats afterwards.

A space consideration with PDML and dictionary managed
tablespaces - each PQ process in your PDML is going to
have its own extent. This extent will begin life with
a size=initial, but will have the empty space trimmed
off at the end of the write, leaving an odd size
extent. Since you are doing PDML, you might have these
extents close together, and when the trim occurs, it
will leave odd sized holes in between and throw off
your space managment strategy. I don't believe that
LMT tablespaces have this issue.

hth,

jack


--- Gurelei <[EMAIL PROTECTED]> wrote:
> Hi all.
> 
> I've been trying to copy a 20mil rows table between
> two databases via insert as select statement. I 
> have dropped all the indices and ran in nologging
> mode
> with hints forcing parallel execution of both ISERT
> and SELECT. While checking the archive directory I
> have noticed that the archives have been created
> every
> 2 minutes. I have cancelled the load and noticed
> that
> I forgot to alter system enable parallel dml so in
> effect the load was going in sequential mode. Then I
> reran my script having added the alter system
> statement and there we no archive created while it
> ran.
> So it looks like even without the indices a
> sequential
> insert as select nologging still creates the
> archives
> wihle the parallel - doesn't. Does it sound right?
> If
> so, why. I thought the nollogging and with no
> indices
> shouldn't produce any log info regardless of the
> mode.
> 
> TIA
> 
> Gene
> 
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