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Message Posted: Fri, 31 Jan 2014 @ 12:37:21 GMT

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Hi Roopalini,

Why don't you try it? You've obviously got the data and an idea of what the query will be. An explain only takes a few seconds.

However, what the plan looks like and the performance will really depend on the query, particularly selection criteria.

As an example, if you've got equality selection criteria against the UPI then almost certainly the plan will be:

- single amp retrieve using the UPI, duplicate the spool file on all amps

- retrieve against the NUSI, with (or without) access to the base row

If however the selection is against the NUSI then probably it will be:

- selection from the NUSI table (with/without using the NUSI)

- "redistribute by hash-code" to join into the second table using the PI.

Cheers,

Dave

Ward Analytics Ltd - Information in motion (www.ward-analytics.com)

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