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Message Posted: Tue, 27 Nov 2007 @ 18:20:39 GMT

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A hot amp indicates that data is skewed. I've had a similar problem in the past, and changing the PI helped.

To select the PI you can use the below query:

     Select hashamp(hashbucket(hashrow(Primary Index))) ,Count(*)
     From MCKSG03_RESP_TBL
     Group By 1;

To check the current skew factor of table use:

     SELECT DatabaseName
     ,TableName
     ,100 * (1 - (AVG(currentperm) / MAX(currentperm))) skew_factor
     FROM dbc.tablesize
     Where TableName  = 'name of your table'
      And DatabaseName    = 'name of your database'
     GROUP BY 1,2
     ORDER BY 1,2;

Regards,

Shubhangi

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