OTL 4.0, Example 708 (XML as varchar_long/otl_long_unicode_string on SELECT, and as varchar_long/otl_long_unicode_string

on INSERT)

This example demonstrates simple INSERT and SELECT statements with the PostgreSQL 8.3 (and higher) XML datatype as well as constant SQL statements. XML columns can be bound with varchar_long variables on INSERT/UPDATE/DELETE. On SELECT, XML gets bound to varchar_long by default.

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_UNICODE // Enable Unicode OTL for ODBC
#if defined(__GNUC__)
#define OTL_UNICODE_CHAR_TYPE unsigned short 
#else
#define OTL_UNICODE_CHAR_TYPE wchar_t
#endif
#include <otlv4.h> // include the OTL 4.0 header file

otl_connect db; // connect object

void insert()
// insert rows into table
{ 
  otl_long_unicode_string f2(80000); // define long unicode string variable
 db.set_max_long_size(80000); // set maximum long string size for connect object
 otl_stream o(10, // buffer size 
              "insert into test_tab values(:f1<int>,:f2<varchar_long>) ",
                 // SQL statement
              db // connect object
             );

 for(int i=1;i<=20;++i){
  f2[0]='<';
  f2[1]='T';
  f2[2]='A';
  f2[3]='G';
  f2[4]='>';
  f2[5]=1111; // Unicode character (decimal code of 1111)  
  f2[6]=2222; // Unicode character (decimal code of 2222)
  f2[7]=3333; // Unicode character (decimal code of 3333)  
  f2[8]=4444; // Unicode character (decimal code of 4444)  
  f2[9]='<';
  f2[10]='/';
  f2[11]='T';
  f2[12]='A';
  f2[13]='G';
  f2[14]='>';
  f2.set_len(15);
  o<<i<<f2;
 }

}

void select()
{ 
 otl_long_unicode_string f2(80000); // define long string variable
 db.set_max_long_size(80000); // set maximum long string size for connect object

 otl_stream i(10, // buffer size
              "select f1, f2 "
              "from test_tab "
              "where f1>=:f11<int> "
              " and f1<=:f12<int>*2",
                 // SELECT statement
              db // connect object
             ); 
   // create select stream
 
 int f1;

 i<<8<<8; // assigning :f11 = 8, :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=";
  for(int j=0;j<f2.len();++j)
    if(f2[j]<128)
      cout<<(char)f2[j];
    else
      cout<<(int)f2[j]<<" ";
  cout<<endl; }

}

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

  db.rlogon("scott/tiger@postgresql2"); // connect to the database

  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 xml)"
    );  // 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 the database

 return 0;

}

Output

f1=8, f2=<TAG>1111 2222 3333 4444 </TAG>
f1=9, f2=<TAG>1111 2222 3333 4444 </TAG>
f1=10, f2=<TAG>1111 2222 3333 4444 </TAG>
f1=11, f2=<TAG>1111 2222 3333 4444 </TAG>
f1=12, f2=<TAG>1111 2222 3333 4444 </TAG>
f1=13, f2=<TAG>1111 2222 3333 4444 </TAG>
f1=14, f2=<TAG>1111 2222 3333 4444 </TAG>
f1=15, f2=<TAG>1111 2222 3333 4444 </TAG>
f1=16, f2=<TAG>1111 2222 3333 4444 </TAG>

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