OTL 4.0, Example 25 (Implicit Select/Result Set returned by a stored procedure)

Example 25 (Implicit Select/Result Set returned by a stored procedure)

This example demonstrates a stored procedure call.

Source Code

#include <iostream.h>
#include <stdio.h>
#define OTL_ODBC // Compile OTL 4.0/ODBC
#include <otlv4.h>

otl_connect db; // connect object

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

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

void select(void)
// fetching result set returned by a stored procedure
{ 
 otl_stream i(50, // buffer size
              "{call my_proc(:f1<int,in>)}",
                 // implicit SELECT statement
              db, // connect object
              otl_implicit_select // implicit SELECT statement
             ); 
   // create select stream
 
 int f1;
 char f2[31];

 i<<8; // assigning :f1 = 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; // assigning :f1 = 4
   // SELECT automatically re-executes when all input variables are
   // assigned. First portion of out 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("uid=scott;pwd=tiger;dsn=mssql"); // 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 varchar(30))"
    );  // create table

  otl_cursor::direct_exec
   (
    db,
    "DROP PROCEDURE my_proc",
    0 // ignore any errors
    );  // drop stored procedure

  otl_cursor::direct_exec
   (
    db,
    "CREATE PROCEDURE my_proc "
    "  @F1 int "
    "AS "
    "SELECT * FROM test_tab "
    "WHERE f1>=@F1 AND f1<=@F1*2 "
    );  // create stored procedure


  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.code<<endl; // print out error code
  cerr<<p.var_info<<endl; // print out the variable that caused the error
  cerr<<p.sqlstate<<endl; // print out SQLSTATE message
  cerr<<p.stm_text<<endl; // print out SQL that caused the error
 }
 db.logoff(); // disconnect from the data source
 return 0;
}

Output

 A=2, B=Test String1

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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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