This example also demonstrates how to use the otl_long_string
class to carry over values from ODBC to OCI8.
#include <iostream>
using namespace std;
#include <stdio.h>
#define OTL_ORA8 // Compile OTL 4.0/OCI8
#define OTL_ODBC // Compile OTL 4.0/ODBC
// In case when <OTL_ORA8,OTL_ODBC> or <OTL_ORA7,OTL_ODBC> pair is
// defined, the OTL header file generates namespaces oracle:: and odbc::
// respectively, in order to make the names of the otl_xxx classes
// unique.
#include <otlv4.h> // include the OTL 4.0 header file
const int long_text_max=70000; // maximum length of long strings.
odbc::otl_connect db1; // connect object
oracle::otl_connect db2; // connect object
void insert1(void)
// insert rows into ODBC table
{
otl_long_string f2(long_text_max); // define long string variable
db1.set_max_long_size(long_text_max); // set maximum long string size for connect object
odbc::otl_stream o(1, // buffer size needs to be set to 1 for long strings
"insert into test_tab values(:f1<int>,:f2<varchar_long>)",
// SQL statement
db1 // connect object
);
for(int i=1;i<=20;++i){
for(int j=0;j<50000;++j)
f2[j]='*';
f2[50000]='?';
f2.set_len(50001);
o<<i<<f2;
}
}
void insert2()
// insert rows into OCI table
{
otl_long_string f2(long_text_max); // define long string variable
db2.set_max_long_size(long_text_max); // set maximum long string size for connect object
int f1;
// INSERT statement for inserting rows into OCI table
oracle::otl_stream
o(1, // buffer size has to be set to 1 for operations with LOBs
"insert into test_tab2 values(:f1<int>,empty_clob()) "
"returning f2 into :f2<clob> ",
// SQL statement
db2 // connect object
);
// SELECT statement to read rows from OCI table
odbc::otl_stream
i(1, // buffer size needs to be set to 1
"select * from test_tab", // SELECT statement
db1 // connect object
);
while(!i.eof()){
i>>f1>>f2; // Reading one row from ODBC
o<<f1<<f2; // Inserting one row into OCI
}
}
void select2()
// Select rows from OCI table
{
otl_long_string f2(long_text_max); // define long string variable
db2.set_max_long_size(long_text_max); // set maximum long string size for connect object
oracle::otl_stream
i(10, // buffer size. To read CLOBs, it can be set to a size greater than 1
"select * from test_tab2 where f1>=:f<int> and f1<=:f*2",
// SELECT statement
db2 // connect object
);
// create select stream
float f1;
i<<8; // assigning :f = 8
// SELECT automatically executes when all input variables are
// assigned. First portion of output rows is fetched to the buffer
while(!i.eof()){ // while not end-of-data
i>>f1>>f2;
cout<<"f1="<<f1<<", f2="<<f2[0]<<f2[f2.len()-1]<<", len="<<f2.len()<<endl;
}
i<<4; // assigning :f = 4
// SELECT automatically executes when all input variables are
// assigned. First portion of output rows is fetched to the buffer
while(!i.eof()){ // while not end-of-data
i>>f1>>f2;
cout<<"f1="<<f1<<", f2="<<f2[0]<<f2[f2.len()-1]<<", len="<<f2.len()<<endl;
}
}
int main()
{
oracle::otl_connect::otl_initialize(); // initialize OCI environment
odbc::otl_connect::otl_initialize(); // initialize ODBC environment
try{
db1.rlogon("UID=scott;PWD=tiger;DSN=my_db"); // connect to ODBC
db2.rlogon("scott/tiger"); // connect to OCI
odbc::otl_cursor::direct_exec
(
db1,
"drop table test_tab",
odbc::otl_exception::disabled // disable OTL exceptions
); // drop table
odbc::otl_cursor::direct_exec
(
db1,
"create table test_tab(f1 number, f2 long)"
); // create table
oracle::otl_cursor::direct_exec
(
db2,
"drop table test_tab2",
oracle::otl_exception::disabled // disable OTL exceptions
); // drop table
oracle::otl_cursor::direct_exec
(
db2,
"create table test_tab2(f1 number, f2 clob)"
); // create table
insert1(); // insert records into MSSQL table
insert2(); // Read the ODBC table and insert records
// into OCI table
select2(); // select records from the Oracle table.
}
catch(odbc::otl_exception& p){ // intercept OTL exceptions
cerr<<p.msg<<endl; // print out error message
cerr<<p.stm_text<<endl; // print out SQL that caused the error
cerr<<p.sqlstate<<endl; // print out SQlSTATE
cerr<<p.var_info<<endl; // print out the variable that caused the error
}
catch(oracle::otl_exception& p){ // intercept OTL exceptions
cerr<<p.msg<<endl; // print out error message
cerr<<p.stm_text<<endl; // print out SQL that caused the error
cerr<<p.var_info<<endl; // print out the variable that caused the error
}
db1.logoff(); // disconnect from ODBC
db2.logoff(); // disconnect from OCI
return 0;
}
f1=8, f2=*?, len=50001
f1=9, f2=*?, len=50001
f1=10, f2=*?, len=50001
f1=11, f2=*?, len=50001
f1=12, f2=*?, len=50001
f1=13, f2=*?, len=50001
f1=14, f2=*?, len=50001
f1=15, f2=*?, len=50001
f1=16, f2=*?, len=50001
f1=4, f2=*?, len=50001
f1=5, f2=*?, len=50001
f1=6, f2=*?, len=50001
f1=7, f2=*?, len=50001
f1=8, f2=*?, len=50001
Copyright © 1996, 2007, Sergei Kuchin, email: skuchin@ispwest.com, skuchin@gmail.com .
Permission to use, copy, modify and redistribute this document for any purpose is hereby granted without fee, provided that the above copyright notice appear in all copies.