Re: db_block_size = 16K inflates tables

You are right! I was specifying segment space management auto, and that causes the inflation. I would expect that to be the default, but according to the documentation it is not. I imagine the growth will slow down after it reaches certain point (??) It is still not clear to me why auto is not recommended in this case...

Thank you!
Ivan.

"Richard Foote" <richard.foote_at_bigpond.com> wrote in message news:zkgA9.75515$g9.212480_at_newsfeeds.bigpond.com...
> Hi Ivan,
>
> I think your "problem" is not associated block size but with the fact you
> are using ASSM. It doesn't insert data in the traditional 'from left to
> right' method but will 'select' an appropriate block from the bitmap
matrix
> and insert the row. As such, these gaps are an issue if you wish to insert
> an initial small number of rows.
>
> Try without ASSM and see how many blocks Oracle uses. You will be pleased
> with the results.
>
> Cheers
>
> Richard
> "ivan vasquez" <ivan_at_itos.uga.edu> wrote in message
> news:aqs1sg$4q3$1_at_cronkite.cc.uga.edu...
> > Hi,
> >
> > I just installed a 9.2.0 instance for GIS applications (ESRI ArcSDE).
The
> > manufacturer suggests using db_block_size = 16K. After a first
> installation
> > using block size 8K, I reinstalled the database using 16K to see if the
> > performance improved. However, a more important problem appeared: Tables
> are
> > growing way too fast.
> >
> > (All tablespaces have been created locally managed, auto segment space
> > mgmt.)
> > In a 8K blocksize tablespace, a table with only 160 rows, 46 bytes per
> row,
> > uses 5 data blocks.
> > In a 16K blocksize tablespace, the exact same table uses 61 data blocks!
> >
> > The tables were created with no storage statements, so defaults should
> > apply. The data was retrieved from user_tables after analyzing them.
> >
> > What could be "wrong"?
> > Thank you,
> > Ivan.
> >
> > Table description:
> >
> > SQL> desc ga_cnt00
> > Name Null? Type
> >
>
> ----------------------------------------- -------- -----------------------
> -
> >
> > OBJECTID NOT NULL NUMBER(10)
> >
> > AREA NUMBER(24,5)
> >
> > COUNTY VARCHAR2(5)
> >
> > NAME VARCHAR2(13)
> >
> > LR_ID NUMBER(16)
> >
> > POP00 NUMBER(16)
> >
> > ID VARCHAR2(5)
> >
> > SHAPE NUMBER(10)
> >
> >
> >
> >
>
>
Received on Wed Nov 13 2002 - 11:04:17 CST