Re: Good DBA please give some technical understanding....

I think your best bet is to read the manual. Why not at least try that. There is a huge amount of information there and pictures even. If you don't have Oracle then you can go to the Oracle Technical Network www.otn.oracle.com and read it there. They are not going to give you the exact information, but a heck of a lot of detail is there. I am only revealing what is already public knowledge (or at least gotten via public methods).

If you want such detailed information you are actually going to have to work for it.
Jim

"cho" <cho_at_sondagsavisen.dk> wrote in message news:qY5Q5.22$ct1.1492_at_news.get2net.dk...
> header with such things as keys ?
> does oracle provide information on their hashing algorithms ?
> have i missed something here ?
>
>
> "Barbara Kennedy" <barbken_at_teleport.com> skrev i en meddelelse
> news:yD4Q5.10923$au.473779_at_nntp3.onemain.com...
> > Blocks are read in their entirety and written in their entirety. There
 is
 a
> > header (small) in each block that holds the info about the block. There
 are
> > chapters on how it decides to write to a block that has data or a new
 one.
> > "Damian" <kndoneill_at_hotmail.com> wrote in message
> > news:Yc3Q5.31536$SF5.552348_at_ozemail.com.au...
> > > For curiosity's sake, I'd like to see the source code (fat chance I
 know).
> > > Therefore, as an exercise in reverse engineering, how would one go
 about
> > > updating a dbf file?
> > >
> > > SELECT Scenario
> > > Selects, updates and deletes would first require a file seek function.
 I
> > > quess you'd have to do a string search first to find the rowid.
> > >
> > > UPDATE Scenario
> > > Well I guess you'd open the dbf with file read, write flags set.
> > > Then you'd search thru the file sequentially, probably moving your
 file
> > > pointer every <block size> until you found your table from the table
 dir
> > > then row from row dir. Then delete <ROWID> from block, (then maybe)
 move
 all
> > > data in block after the deletion up to where the rowid before the
 deleted
> > > one ends. finally, write your updated row at the end of the last row
 in
 the
> > > block.
> > >
> > > INSERT Scenario
> > > Say a new row is to be inserted into the table.Is it going to be
 inserted
 at
> > > the END of block (which?) assigned for the Table. What will happen if
 the
> > > Block is consumed and a new block is going to be created. Where the
 new
> > > block is going to be created and how it will effect the performance
 when
 the
> > > blocks are split across separated by different blocks.
> > >
> > > DELETE Scenario:
> > > Same as update without the write function at the end.
> > >
> > > "Barbara Kennedy" <barbken_at_teleport.com> wrote in message
> > > news:D61Q5.10839$au.438196_at_nntp3.onemain.com...
> > > > If you are just looking for it conceptually the manual (available in
 Html
> > > > format on the CD ) Oracle Concepts manual. If you are asking so you
 can
 get
> > > > at the data directly then don't do it! If you need to get at the
 data
> > > > directly (by scanning the file directly) write your own dbms; don't
 use
 a
> > > > commercial dbms and try to subvert it. You will only cause yourself
 great
> > > > pain. The manuals don't go into enough details to reverse engineer
 it.
> > > > Jim
> > > > "Pravesh Godiyal" <namia_at_hotmail.com> wrote in message
> > > > news:Sj0Q5.31459$SF5.549328_at_ozemail.com.au...
> > > > > Is there any one aware or could share the knowledge as how oracle
 store
 the
> > > > > table-reocrds into dbf files.
> > > > > How it access the data in the dbf files.
> > > > >
> > > > > Cheers
> > > > > Namia
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>
Received on Tue Nov 14 2000 - 09:17:01 CST