Hi, > Whenever I have done comparisons of different sql to produce the same > result, the bytes sent via SQL*Net were always the same - maybe wrong, > but at least consistently wrong. I completely agree. I performed some tests with sample query (that return the length of its own statement in bytes) select (count(*)-1) * length('select * from dual union all ') + 94 from ( select * from dual union all select * from dual union all select * from dual union all select * from dual union all select * from dual union all < add some rows here to get different statement lengths> select * from dual ); Bytes received seems to have a systematic error (the value is about 1KB *less* then the length of SQL statement) , so small values are probably meaningless. Bytes sent seems to be - in this count(*) case - stabile. Note the switch from 345 to 346 for higher numbers. Regards Jaromir Some results - Length of SQL Statement compared with bytes received (COUNT(*)-1)*LENGTH('SELECT*FROMDUALUNIONALL')+94 ------------------------------------------------- 239 345 bytes sent via SQL*Net to client 503 bytes received via SQL*Net from client (COUNT(*)-1)*LENGTH('SELECT*FROMDUALUNIONALL')+94 ------------------------------------------------- 1254 345 bytes sent via SQL*Net to client 503 bytes received via SQL*Net from client (COUNT(*)-1)*LENGTH('SELECT*FROMDUALUNIONALL')+94 ------------------------------------------------- 2414 345 bytes sent via SQL*Net to client 1121 bytes received via SQL*Net from client (COUNT(*)-1)*LENGTH('SELECT*FROMDUALUNIONALL')+94 ------------------------------------------------- 4734 345 bytes sent via SQL*Net to client 3477 bytes received via SQL*Net from client (COUNT(*)-1)*LENGTH('SELECT*FROMDUALUNIONALL')+94 ------------------------------------------------- 9374 345 bytes sent via SQL*Net to client 8190 bytes received via SQL*Net from client (COUNT(*)-1)*LENGTH('SELECT*FROMDUALUNIONALL')+94 ------------------------------------------------- 18654 346 bytes sent via SQL*Net to client 17615 bytes received via SQL*Net from client (COUNT(*)-1)*LENGTH('SELECT*FROMDUALUNIONALL')+94 ------------------------------------------------- 130014 346 bytes sent via SQL*Net to client 130715 bytes received via SQL*Net from client ----- Original Message ----- From: "Wolfgang Breitling" <breitliw@xxxxxxxxxxxxx> To: "Cary Millsap" <cary.millsap@xxxxxxxxxx> Cc: <yasbs@xxxxxxxxxxxxxx>; <oracle-l@xxxxxxxxxxxxx> Sent: Wednesday, February 02, 2005 4:49 PM Subject: Re: cpu time and query column in tkprof output -- //www.freelists.org/webpage/oracle-l