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Message Posted: Tue, 12 Feb 2002 @ 16:49:31 GMT

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Subj:   Re: Insert data into table
From:   Andres Del Villar

Our tables have only UPI. I deleted statistics because i need to know if the process is better or worse than tables with statistics. I know that the statistics are usefull for client-queries, but in my particular case, and only in this moment, i'm testing several choices for resolve my problem.

The explain for one on our queries is

INSERT INTO ventas.talineadetalle
FROM temporal.talineadetalletemp

  1)First, we lock a distinct Temporal."pseudo table" for read on a RowHash to prevent global deadlock for Temporal.taLineaDetalleTemp.  
  2)Next, we lock a distinct Ventas."pseudo table" for write on a RowHash to prevent global deadlock for Ventas.taLineaDetalle.  
  3)We lock Temporal.taLineaDetalleTemp for read, and we lock Ventas.taLineaDetalle for write.  
  4)We do an all-AMPs RETRIEVE step from Temporal.taLineaDetalleTemp by way of an all-rows scan with no residual conditions into Spool 1, which is built locally on the AMPs. Then we do a SORT to order Spool 1 by row hash. The size of Spool 1 is estimated with low confidence to be 237,492 rows. The estimated time for this step is 1 minute and 37 seconds.  
  5)We do a MERGE into Ventas.taLineaDetalle from Spool 1 (Last Use).  
  6)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.  

This table have only a UPI

This sentence take around 50 minutes and insert only 300.000 rows app.


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