Pro*C slow fetch compared to sqlplus

Question

It takes 36 seconds to retrieve the table contents with Pro*C, while with sqlplus it takes only 9 seconds.
I'm connecting via a chain of ssh servers. The scp tool copies files at speed 10Mbit.
How to make the fetch faster?
time echo "SELECT COUNTRY_CODE || NETWORK_CODE,OPERATOR_ID FROM RAPOPERATOR ORDER BY  'x'||COUNTRY_CODE || NETWORK_CODE;" | sqlplus -L rap/rap@RAP
COUNTRY_CODE||N OPERATOR_ID
ZWEN1                   293
ZWEN3                   436
4179                      1
729 rows selected.
SQL> Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,
Data Mining and Real Application Testing options
real    0m9.640s
user    0m0.000s
sys     0m0.015s
char mccmnc[20+1];
int oper;
EXEC SQL DECLARE sel_perftest CURSOR FOR SELECT COUNTRY_CODE || NETWORK_CODE,OPERATOR_ID FROM RAPOPERATOR ORDER BY  'x'||COUNTRY_CODE || NETWORK_CODE;
applog(PITS_INFO,"before open");
EXEC SQL OPEN sel_perftest;
applog(PITS_INFO,"after open");
for(;;) {
  EXEC SQL FETCH sel_perftest into :mccmnc, :oper;
  if (sqlca.sqlcode == DB_NOTFOUND) break;
applog(PITS_INFO,"after fetch");
13JAN21@08:22:06.092,before open
13JAN21@08:22:06.191,after open
13JAN21@08:22:42.890,after fetchEdited by: 940607 on 21.01.2013 0:37

Answer 1

EXEC ORACLE OPTION (PREFETCH=100);solved the problem