# OTL 4.0, Example 401 (Datatype override in SELECT, Sybase SQL Server)

This example demonstrates a SELECT statement with a numeric column, being converted into a null terminated string. It is a useful technique when there is a need to read and write numbers, which are larger than 16 digits.

## Source Code

    #include <iostream>
    using namespace std;

    #include <stdio.h>

    #define OTL_ODBC_UNIX // Compile OTL 4.0/ODBC
    #include <otlv4.h> // include the OTL 4.0 header file

    otl_connect db; // connect object

    void insert()
    // insert rows into table
    {
     otl_stream o(50, // buffer size
                  "insert into test_tab values(12345678900000000+convert(numeric,:f1<int>),:f2<char[31]>)",
                     // SQL statement
                  db // connect object
                 );
     char tmp[32];

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

    void select()
    {
     otl_stream i;

     i.set_column_type(1,otl_var_char,40); // use a string(40) instead of default double
     i.open(50, // buffer size
            "select * from test_tab "
            "where f1>=12345678900000000+convert(numeric,:f11<int>) "
            "  and f1<=12345678900000000+convert(numeric,:f12<int>)*2",
               // SELECT statement
            db // connect object
           );
       // create select stream

     char f1[40];
     char f2[31];

     i<<8<<8; // assigning :f11, :f12 = 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 :f11, :f12 = 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("scott/tigger@sybsql"); // 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 numeric, 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.var_info<<endl; // print out the variable that caused the error
     }

     db.logoff(); // disconnect from ODBC

     return 0;

    }

## Output

    f1=12345678900000008, f2=Name8
    f1=12345678900000009, f2=Name9
    f1=12345678900000010, f2=Name10
    f1=12345678900000011, f2=Name11
    f1=12345678900000012, f2=Name12
    f1=12345678900000013, f2=Name13
    f1=12345678900000014, f2=Name14
    f1=12345678900000015, f2=Name15
    f1=12345678900000016, f2=Name16
    f1=12345678900000004, f2=Name4
    f1=12345678900000005, f2=Name5
    f1=12345678900000006, f2=Name6
    f1=12345678900000007, f2=Name7
    f1=12345678900000008, f2=Name8

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Copyright © 1996, 2007, Sergei Kuchin, email: skuchin@ispwest.com, skuchin@gmail.com/a>.

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.