OTL 4.0, Example 465 (Simple Insert/Select with BYTEA and otl_stream_read_iterator)

This example demonstrates simple INSERT and SELECT statements with the BYTEA datatype as well as constant SQL statements.

Source Code

#include <iostream>
using namespace std;

#include <stdio.h>

// #define OTL_ODBC_UNIX // uncomment this line if UnixODBC is used
#define OTL_ODBC_ALTERNATE_RPC
#if !defined(_WIN32) && !defined(_WIN64)
#define OTL_ODBC
#else 
#define OTL_ODBC_POSTGRESQL // required with PG ODBC on Windows
#endif
#define OTL_STREAM_READ_ITERATOR_ON
#include <otlv4.h> // include the OTL 4.0 header file

otl_connect db; // connect object

void insert()
// insert rows into table
{

 otl_long_string f2(700); // define long string variable
 otl_stream o(50, // buffer size can be > 1 for PostgreSQL 8.1 and higher
              "insert into test_tab values(:f1<int>,:f2<raw[700]>)",
                 // SQL statement
              db // connect object
             );
 for(int i=1;i<=20;++i){
  for(int j=0;j<699;++j)
   f2[j]='*';
  f2[699]='?';
  f2.set_len(700);
  o<<i<<f2;
 }

}

void select()
{ 
 otl_long_string f2(700); // define long string variable
 otl_stream i(10, // buffer size
              "select "
              "  f1, "
              "  f2 :#2<raw[700]> "
// f2's type has to be overriden for PG ODBC, Linux
              "from test_tab "
              "where f1>=:f11<int> and f1<=:f12<int>*2",
                 // SELECT statement
              db // connect object
             ); 
   // create select stream
 
 int f1;
 otl_stream_read_iterator<otl_stream,otl_exception,otl_lob_stream> rs;

 i<<8<<8; // assigning :f11 = 8, :f12 = 8
 rs.attach(i); // attach the iterator "rs" to the stream "i".
   // SELECT automatically executes when all input variables are
   // assigned. First portion of output rows is fetched to the buffer

 while(rs.next_row()){ // while not end-of-data
  rs.get(1,f1);
  rs.get(2,f2);
  cout<<"f1="<<f1<<", f2="<<f2[0]<<f2[f2.len()-1]<<", len="<<f2.len()<<endl;
 }

 i<<4<<4; // assigning :f11 = 4, :f12 = 4
   // SELECT automatically executes when all input variables are
   // assigned. First portion of output rows is fetched to the buffer

 while(rs.next_row()){ // while not end-of-data
  rs.get(1,f1);
  rs.get(2,f2);
  cout<<"f1="<<f1<<", f2="<<f2[0]<<f2[f2.len()-1]<<", len="<<f2.len()<<endl;
 }

 rs.detach(); // detach the itertor from the stream

}

int main()
{
 otl_connect::otl_initialize(); // initialize the database API environment
 try{

  db.rlogon("scott/tiger@postgresql"); // connect to the database

  otl_cursor::direct_exec
   (
    db,
    "drop table test_tab",
    otl_exception::disabled // disable OTL exceptions
   ); // drop table
  db.commit();
  otl_cursor::direct_exec
   (
    db,
    "create table test_tab(f1 int, f2 bytea)"
    );  // create table
  db.commit();
  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.sqlstate<<endl; // print out SQLSTATE 
  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
 }

 db.logoff(); // disconnect from the database

 return 0;

}

Output

f1=8, f2=*?, len=700
f1=9, f2=*?, len=700
f1=10, f2=*?, len=700
f1=11, f2=*?, len=700
f1=12, f2=*?, len=700
f1=13, f2=*?, len=700
f1=14, f2=*?, len=700
f1=15, f2=*?, len=700
f1=16, f2=*?, len=700
f1=4, f2=*?, len=700
f1=5, f2=*?, len=700
f1=6, f2=*?, len=700
f1=7, f2=*?, len=700
f1=8, f2=*?, len=700

Examples Contents Go Home

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. THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.