Re: why db block gets = 0?

Seems like the usual confusion over DB BLOCK GETS and CONSISTENT GETS. Lots of AskTom resources for that, one of which is:

http://asktom.oracle.com/pls/ask/f?p=4950:8:3827657808746015643::NO::F4950_P8_DISPLAYID,F4950_P8_CRITERIA:865586003021,

Cheers!

niy38_at_hotmail.com (Niy) wrote in message news:<55dd405a.0410081202.6203b398_at_posting.google.com>...
> 9.2.0.5 version
>
> when I connect as hr and turn trace on:
> select * from regions;
>
> output:
>
>
> ......
>
> Execution Plan
> ----------------------------------------------------------
> 0 SELECT STATEMENT Optimizer=CHOOSE (Cost=2 Card=4 Bytes=56)
> 1 0 TABLE ACCESS (FULL) OF 'REGIONS' (Cost=2 Card=4 Bytes=56)
>
>
>
>
> Statistics
> ----------------------------------------------------------
> 0 recursive calls
> 0 db block gets
> 4 consistent gets
> 0 physical reads
> 0 redo size
> 534 bytes sent via SQL*Net to client
> 499 bytes received via SQL*Net from client
> 2 SQL*Net roundtrips to/from client
> 0 sorts (memory)
> 0 sorts (disk)
> 4 rows processed
>
>
>
> If it's first time I can see physical reads not equal to 0.
>
> My confusion is:
> 1) I never update regions tables, why there is consistents gets?
> 2) why db block gets is 0 ? it should have some value because
> I'm reading blocks in current mode.
>
> Thanks for clarification!
Received on Fri Oct 08 2004 - 23:00:47 CDT