OTL 4.0, Example 82 (otl_long_string container and LONGBLOB column)

Example 82 (otl_long_string container and LONBLOB column)

This example demonstrates simple INSERT/SELECT with otl_long_string container and LONGBLOB column. TINYBLOB, BLOB, MEDIUMBLOB can be used in this example as well.

Source Code

#include <iostream.h>
#include <stdio.h>
#define OTL_ODBC_MYSQL // Compile OTL 4.0/MyODBC
// #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(void)
// insert rows into table
{ 

 otl_long_string f2(70000); // define long string variable
 db.set_max_long_size(70000); // set maximum long string size for connect object

 otl_stream o(1, // buffer size needs to be set to 1
              "insert into test_tab values(:f1<int>,:f2<raw_long>)", 
                 // INSERT statement
              db // connect object
             );


 for(int i=1;i<=10;++i){
  for(int j=0;j<50000;++j)
   f2[j]='*';
  f2[50000]='?';
  f2.set_len(50001);
  o<<i<<f2;
 }
}

void select(void)
{ 
 otl_long_string f2(70000); // define long string variable
 db.set_max_long_size(70000); // set maximum long string size for connect object

 otl_stream i(1, // buffer size needs to be set to 1 in case of BLOB columns
              "select * from test_tab",
                 // SELECT statement
              db // connect object
             ); 
   // create select stream
 
 int f1;


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

  db.rlogon("UID=scott;PWD=tiger;DSN=mysql"); // 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 longblob)"
    );  // 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 ODBC

 return 0;

}

Output

f1=1, f2=*?, len=50001
f1=2, f2=*?, len=50001
f1=3, 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
f1=9, f2=*?, len=50001
f1=10, f2=*?, len=50001

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Copyright © 1996, 2001, Sergei Kuchin, email: [email protected], [email protected] .

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.

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