Re: insert/update performance

johnnie,
here is the stat for two statement. I think dual is more expensive. because the recursive call. db block gets may misleading because two statements were execute one after another. Ted Chyn

SQL> insert into ted1 values('a','b');

1 row created.

Statistics

          8  recursive calls
         11  db block gets
          2  consistent gets
          0  physical reads
        560  redo size
        396  bytes sent via SQL*Net to client
        549  bytes received via SQL*Net from client
          3  SQL*Net roundtrips to/from client
          2  sorts (memory)
          0  sorts (disk)
          1  rows processed

SQL> insert into ted1 select 'a','b' from dual;

1 row created.

Statistics

         28  recursive calls
          4  db block gets
          5  consistent gets
          0  physical reads
        212  redo size
        396  bytes sent via SQL*Net to client
        558  bytes received via SQL*Net from client
          3  SQL*Net roundtrips to/from client
          1  sorts (memory)
          0  sorts (disk)
          1  rows processed

SQL>
In article <7m2627$5nq$2_at_imsp009a.netvigator.com>,   Norris <johnnie_at_cooper.com.hk> wrote:
> May I know if there is any performance difference for the following
two
> statement (with and without subquery):
>
> insert into table1 select 'a','b' from dual;
>
> insert into table1 values ('a','b');
>

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Share what you know. Learn what you don't. Received on Thu Jul 08 1999 - 09:25:21 CDT