ex278_odbc.cpp

使用otl开发的数据库应用包

#include <iostream>
using namespace std;

#include <stdio.h>

#define OTL_ODBC // Compile OTL 4.0/ODBC
#define ODBCVER 0x0250 // ODBC Version # needs to be downgraded
                       // to 2.5 because the SQLite ODBC driver is
                       // not up to the ODBC 3.5 level just yet
// #define OTL_ODBC_UNIX // uncomment this line if UnixODBC is used
#include <otlv4.h> // include the OTL 4.0 header file


otl_connect db; // connect object

void insert()
// insert rows into table
{ 
 // open a stream with no implicit committing
 otl_nocommit_stream 
   o(50, // buffer size
     "insert into test_tab values(:f1<float>,:f2<char[31]>)", 
         // SQL statement
     db // connect object
    );
 char tmp[32];

 otl_cursor::direct_exec(db,"BEGIN TRANSACTION");
    // begin transaction. This explicit construct needs to be used 
    // because the ODBC driver could eventually run into the 
    // "Function Sequence Error" error.

 for(int i=1;i<=100;++i){
  sprintf(tmp,"Name%d",i);
  o<<tmp<<i;
 }

 o.flush(); // flush the stream buffer to make sure that 
            // all rows get to the table
 otl_cursor::direct_exec(db,"COMMIT TRANSACTION");
    // commit transaction
}

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

  db.rlogon("scott/tiger@sqlite",1);
    // connect to the database and set the auto-commit to on. 
    // The auto-commit is needed to make "BEGIN TRANSACTION" / 
    // "COMMIT TRANSACTION" work properly.

  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

 }

 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 ODBC

 return 0;

}