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Message Posted: Thu, 18 Jan 2007 @ 11:53:55 GMT

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Informatica's push-down is not fully developed yet, however it works for quite a few of the cases IF you use full-source qualifier SQL overrides. Informatica's support of Teradata OLAP functions is non-existent today. Informatica cannot push-down sequence generation to the database, requiring again - SQL overrides with ROW_NUMBER and PARTITION BY OLAP functionality.

The requirements for full 100% push-down are very strict. Here are a few of them: 1) source and target database connection MUST be the same, this forces you to use VIEWS in Teradata that cross databases via ownership. Make the views 1:1 with the underlying table structures, so that UPDATES work as well. 2) Mark the sessions as FULL-PUSHDOWN WITH VIEW, as without view creation, sometimes it doesn't work properly. 3) you can use the joiner, and lookup and limited expressions (such as ISNULL) which are converted to COALESCE(). But any complex expressions using unconnected lookups break the push-down.

Cheers,

Dan Linstedt
CTO, Myers-Holum, Inc
www.MyersHolum.com

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