Re: One for the gurus

Marc Mazerolle wrote:

> They should be matching the SQL processing steps :
>
> (see inline)
>
> Ivan Bajon wrote:
>
> > I've been asked to explain in detail how SQL*Net transfers data. So I tried
> > running this simple query with trace level 16 turned on:
> >
> > select 1 from dual;
> >
> > I ran the query on Oracle7.3.4 using SQL*Plus 3.3.4 (in blocking mode to
> > avoid a million "transport read error"s and with SQL*Net 2.3.4. The UNP is
> > TCP/IP (default packet size), the OS is WinNT4 in both ends, and the SDU is
> > default (2K I think).
> > The trace file shows the following packet transfers (given in level 6
> > output):
> >
> >
>
> SELECT statement is sent to server to be parsed
>
> > 134 bytes to transport
>
> Result of parsing returned to client
>
> > 70 bytes from transport
>
> No binding required for this specific select. So Open cursor on result set
>
> > 49 bytes to transport
>
> Cursor returned
>
> > 45 bytes from transport
>
> Request to fetch first row
>
> > 117 bytes to transport
>
> Return first row
>
> > 102 bytes from transport
> >
> > The first packet contains my statement and some overhead. The following two
> > look very binary. Then follows what I believe is the result. I cannot
> > identify the 5th either. The 6th contains an error message "no data found".
> > Could anyone please either direct me towards a precise and thorough
> > source of information regarding the behaviour of SQL*Net or tell me
> >
> > 1) What do the above packets 2, 3, 5, and 6 contain?
> > 2) How are the packets organized? How much is header and where etc.
> >
> > Any help very much appreciated & guaranteed to include you in my evening
> > prayer. :o) I've searched through documentation, Metalink, Technet etc. I've
> > haven't been able to find anything that goes into this much detail.
> >
> > Ivan Bajon
>
> My intepretation is opened to critics. I have no ideas on the format of the
> messages.
>
> Regards,
>
> Marc Mazerolle
> InforMaze Technologies

If I remember correctly, Oracle 8 Design... from O'Reilly have about 5-10 pages of sqlnet working but no inner detail just what is done at each step for a query. Received on Tue Mar 30 1999 - 10:35:48 CST