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Re: Unusually high number of current mode reads for a GTT insert

From: VC <boston103_at_hotmail.com>
Date: Tue, 02 Mar 2004 22:23:41 GMT
Message-ID: <JP71c.101707$Xp.434543@attbi_s54>


Actually, joins have got nothing to do with the problem. A plain insert will do the same:

SQL> insert into t13 select t11.object_id, t11.object_name from t11;

3030 rows created.

Statistics


         40  recursive calls
        201  db block gets
         79  consistent gets
          0  physical reads
     102848  redo size
        620  bytes sent via SQL*Net to client
        562  bytes received via SQL*Net from client
          3  SQL*Net roundtrips to/from client
          1  sorts (memory)
          0  sorts (disk)
       3030  rows processed


... versus:

SQL> insert into t13_tmp select t11.object_id, t11.object_name from t11;

3030 rows created.

Statistics


          0  recursive calls
       3120  db block gets
         51  consistent gets
          0  physical reads
     389312  redo size
        620  bytes sent via SQL*Net to client
        569  bytes received via SQL*Net from client
          3  SQL*Net roundtrips to/from client
          1  sorts (memory)
          0  sorts (disk)
       3030  rows processed

The number of the current mode gets is 3120 vs. 201 for an ordinary table. The redo, counter-intuitively, is also quite high for a GTT.

VC Received on Tue Mar 02 2004 - 16:23:41 CST

Original text of this message

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