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Message Posted: Wed, 21 Mar 2012 @ 15:35:14 GMT


     
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Subj:   Re: How records get hashed if PI value is NULL?
 
From:   Fenwick, Ruth

It will assign to the amp that NULL hashes to. It is not always the highest numbered AMP, particularly on systems with more than 256 AMPS.

Also note, zero and spaces usually hash to the same amp as null.

You can check what AMP it hashes to as follows:

     SEL HASHAMP(HASHBUCKET(HASHROW( 0)));
     SEL HASHAMP(HASHBUCKET(HASHROW( ' ' )));
     SEL HASHAMP(HASHBUCKET(HASHROW( NULL )));

You can check how many amps you have as follows (remember it starts numbering at 0):

     SEL HASHAMP();


     
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