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Message Posted: Tue, 04 Apr 2006 @ 20:07:40 GMT

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The hashing algorithm delivers a 4 byte row hash.

The higher 2 byte are the DSW that determines the AMP, using the 65,536 entry Hash Map. Just because the rows end up on the same AMP or have the same DSW doesn't make this a hash collision.

The hash collision can occur on the AMP when the full 4 byte row hash is the same; and there are some 4.2 billion values.

Best regards,

Tom Fastner
Senior Consultant
Teradata Certified Master
Teradata
A Division of NCR

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