Re: Informatica load modes

From: Kurt Franke <Kurt-Franke_at_web.de>
Date: Wed, 20 May 2009 13:18:54 +0200
Message-Id: <1229371676_at_web.de>


Greg,

> Would someone who is experienced with Informatica explain what the
> difference is between "bulk mode" and "normal mode" and when one would
> use either?
> I would like to use PDML as well as direct path loads (insert /*+
> append */) and am wondering if this mode controls that (or what it
> exactly controls).
> Any other advice on how to leverage Informatica for an Oracle platform
> would be appreciated.

Direct load insert needs the input from a select statement and is not possible with a VALUE clause.
Thus it cannot be used by Tools like Informatica. (Yes, they are handicapped in comparison to do the work inside the database)

If they speek about bulk insert the use something similar to the PL/SQL "FORALL" clause and effectively handle an array of rows at once. This will reduce the number of network round trips and also reduce the number of switches into sql mode (soft parse)

Hence it has more performance than single row inserts.

But it has much less performance than a direct load insert which didn't write undo records and possible can avoid writing redo log when nologging is set on the target table (this does make sense for working tables which are truncated after the work is done and the data are moved to a real target table)

Regards

kf

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Received on Wed May 20 2009 - 06:18:54 CDT

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