One for the gurus

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):

134 bytes to transport
70 bytes from transport
49 bytes to transport
45 bytes from transport
117 bytes to transport
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 Received on Mon Mar 29 1999 - 14:52:11 CST