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Message Posted: Thu, 02 Jul 2009 @ 08:29:44 GMT


     
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Subj:   Explain plan for a Delete
 
From:   visakh.crv

In the explain plan for a delete, I saw the following line:

" We spoil the parser's dictionary cache for the table."

Can anyone throw some light on this?

here's the entire plan for the Delete:

Explanation
--------------------------------------------------
 
  1)First, we lock a distinct DBNAME."pseudo table" for write on a RowHash to prevent global deadlock for TABLENAME.  
  2)Next, we lock TABLENAME for write.  
  3)We do an all-AMPs DELETE from TABLENAME by way of an all-rows scan with no residual conditions. The size is estimated with high confidence to be 11,824,115 rows. The estimated time for this step is 0.36 seconds.  
  4)We spoil the parser's dictionary cache for the table.  
  5)Finally, we send out an END TRANSACTION step to all AMPs involved in processing the request.  
  ->No rows are returned to the user as the result of statement 1. No rows are returned to the user as the result of statement 2.  


Thanks,

Visakh C R
India



     
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