OTL 4.0, Example 697 (Skipping to the end of the row with otl_stream::skip_to_end_of_row())

This example demonstrates the otl_stream::skip_to_end_of_row() function. The function can be useful when there is a need to skip to the end of the current row in a fetch sequence, instead of read the remaining column values. Skipping to the end of the row is more efficient in that case.

Source Code

#include <iostream>
using namespace std;

#include <stdio.h>

#define OTL_ODBC_MSSQL_2008 // Compile OTL 4.0/MS SQL 2008 SNAC
#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(: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(50, // buffer size
              "select * from test_tab where f1>=:f11<int> and f1<=:f12<int>*2",
                 // SELECT statement
              db // connect object
             ); 
   // create select stream
 
 int f1;
 char f2[31];

 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(!i.eof()){ // while not end-of-data
  i>>f1;
  if(f1==4){
    i>>f2;
    cout<<"f1="<<f1<<", f2="<<f2<<endl;
  }else{
    i.skip_to_end_of_row(); // skipping to the end of the row
                            // when there is no need to read the remaining
                            // column values of the row
    cout<<"f1="<<f1<<", skipping the rest of the row"<<endl;
  }
 }

}

int main()
{
 otl_connect::otl_initialize();
 try{

  db.rlogon("scott/tiger@mssql2008"); // 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 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 the database

 return 0;

}

Output

f1=4, f2=Name4
f1=5, skipping the rest of the row
f1=6, skipping the rest of the row
f1=7, skipping the rest of the row
f1=8, skipping the rest of the row

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