"Howard J. Rogers" <hjr_at_dizwell.com> wrote in message news:<4069f1ef$0$25655$afc38c87_at_news.optusnet.com.au>...
> "Ed Stevens" <nospam_at_noway.nohow> wrote in message
> news:kaoj60l8iif2nikvapuk5vanp361s4qmme_at_4ax.com...
> > Correction: Oracle 8.1.7.4
> >
> > On Tue, 30 Mar 2004 15:00:13 -0600, Ed Stevens <nospam_at_noway.nohow>
> > wrote:
> >
> > >Oracle 8.1.4 on Win2k
> > >
> > >Created a test tablespace. LMT w/ uniform extents.
> > >Created table and pk index in the new TS
> > >Ran a PL/SQL loop to load the new table with test data.
> > >
> > >Then ran the following query:
> > >
> > >select supl_key "key",
> > > dbms_rowid.rowid_block_number(rowid) "block",
> > > dbms_rowid.rowid_row_number(rowid) "row"
> > >from mytable
> > >order by supl_key
> > >/
> > >
> > >I was somewhat surprised to find that the lowest # block-id was 18.
> > >Am I right in thinking that blocks 1 thru 17 are used for TS
> > >management?
>
> Let me guess. You are using 4K Oracle blocks?
>
> You are close, but not quite.
>
> One of those 17 blocks is the data file header block (SCNs and all that).
> The other 16 will indeed be the tablespace bitmap (16 blocks at 4K each
> makes 64K. All LMTs start out with 64K pinched for the bitmap in this way).
>
> Regards
> HJR
Yes, 4k blocks. That explains that very neatly. Thank you.
Received on Wed Mar 31 2004 - 10:19:38 CST
