terminate called after throwing an instance of 'otl_tmpl_exception<otl_exc, otl_解决方法

terminate called after throwing an instance of 'otl_tmpl_exception<otl_exc, otl_
#include <iostream>
using namespace std;
#include <stdio.h>

#define OTL_ODBC // Compile OTL 4/ODBC
#include <otlv4.h> // include the OTL 4 header file

otl_connect db; // connect object

void insert()
// insert rows into table
{ 
 otl_stream o(50, // buffer size
  "insert into test_tab values(:f1<float>,:f2<char[31]>)", 
  // SQL statement
  db // connect object
  );
 char tmp[32];

 for(int i=1;i<=100;++i){
#if defined(_MSC_VER)
#if (_MSC_VER >= 1400) // VC++ 8.0 or higher
  sprintf_s(tmp,sizeof(tmp),"Name%d",i);
#else
  sprintf(tmp,"Name%d",i);
#endif
#else
  sprintf(tmp,"Name%d",i);
#endif
  o<<static_cast<float>(i)<<tmp;
 }
}

void select()
{ 
 otl_stream i(50, // buffer size
  "select * from test_tab where f1>=:f<int> and f1<=:ff<int>*2",
  // SELECT statement
  db // connect object
  ); 
  // create select stream
 
 float f1;
 char f2[31];

 i<<8<<8; // assigning :f = 8; :ff = 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<<endl;
 }

 i<<4<<4; // assigning :f = 4, :ff = 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<<endl;
 }

}

int main()
{
 otl_connect::otl_initialize(); // initialize ODBC environment
 try{

  db.rlogon("UID=scott;PWD=tiger;DSN=my_db"); // connect to ODBC

  otl_cursor::direct_exec
  (
  db,
  "drop table test_tab",
  otl_exception::disabled // disable OTL exceptions
  ); // drop table

  otl_cursor::direct_exec
  (
  db,
  "create table test_tab(f1 int, f2 varchar(30))"
  ); // create table

  insert(); // insert records into table
  select(); // select records from table

 }

 catch(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 message
  cerr<<p.var_info<<endl; // print out the variable that caused the error
 }

 db.logoff(); // disconnect from Oracle

 return 0;

}


#g++ ex21_odbc.cpp -lodbc

#./a.out
出现如下错误：
[unixODBC][Driver Manager]Data source name not found, and no default driver specified

IM002

terminate called after throwing an instance of 'otl_tmpl_exception<otl_exc, otl_conn, otl_cur>'
已放弃


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