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Message Posted: Thu, 26 Jun 2003 @ 14:00:26 GMT


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Subj:		Re: Create Table Efficiencies

From:		Jim Downey

Ray,

Two things to keep an eye on: Distribution and redistribution.

Is your data distributed evenly across all amps? if you data lumps to one amp, one amp works while the rest sit idle. it is possible your create table is lumping your data to an amp. specify a primary index that distributes the data.

When joining tables on different primary indexes are redistributed (moved) to accomplish the join. Statistics are used by the optimizer to make sure the most efficient method is used.

I use the create table as syntax and have not had any problems.

Jim