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Message Posted: Fri, 09 Nov 2001 @ 15:35:10 GMT


     
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Subj:   Re: Rehash on a restore
 
From:   Dieter Nöth

  I'm looking for someone who has some experience with doing restores after a hardware upgrade.  


Don't ask me ;-)


  Last year we did an upgrade that required a sysint (you think I'd be good t them by now). My restores took about the same amount of time as my archives, but were running on a machine 3 times faster (1 node to 3 nodes).  


  The restores from the last upgrade had messages as follows:  


  *** Warning 3803:Table 'B_MB_DETAIL' already exists.
NEED TO RE-HASH ROWS
STARTING TO RESTORE TABLE "HBCADM"."B_MB_DETAIL"
 


  I would have expected the same kind of message restoring from one system to another - after all they have a different hash map.  


A different hash map, but the same hashing algorithm. When you SYSINITed, you probably used the new Universal Hash, so all rowhashes had to be recalculated.

When you restore to a system with different AMPs, then the rowhashes stay the same, the rows are only redistributed across all AMP.


Dieter



     
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