Connect C++ with Oracle

Oracle C++ Call Interface (OCCI) is an Application Programming Interface (API) that provides C++ applications access to data in an Oracle database. This API is a significant improvement to the Oracle Call Interface (OCI) API as far as ease of use is concerned. Engineers who have written JDBC (Java Database Connectivity) code will find the OCCI API to be quite similar to that of JDBC

1) The table that is used in the example code is:

Code:

create table EMP(
	empno     NUMBER,
	ename     VARCHAR2(10),
	hireDate  Date);

2) Database Query : Select the contents of the EMP table

Code:

#include <DbManager.h>
#include <iostream>

using namespace std;

using namespace oracle::occi;

const string sqlString("select empno, ename, hiredate from emp");

const string dateFormat("DD-MON-YYYY HH24:MI:SS");

int main(int argc, char **argv)

{
	if (argc != 2)
	{
		cerr << "\nUsage: " << argv[0] << " <db-user-name>\n" << endl;
		exit(1);
	}
	
	// Initialize OracleServices
	
	DbManager* dbm = NULL;
	
	OracleServices* oras = NULL;
	
	Statement *stmt = NULL;
	
	ResultSet *resultSet = NULL;
	
	try
	{
		
		// Obtain OracleServices object with the default args.
		
		dbm = new DbManager(userName);
		
		oras = dbm->getOracleServices();
		
		// Obtain a cached connection
		
		Connection * conn = oras->connection();
		
		// Create a statement
		
		stmt = conn->createStatement(sqlString);
		
		int empno;
		
		string ename;
		
		Date hireDate;
		
		string dateAsString;
		
		// Execute query to get a resultset
		
		resultSet = stmt->executeQuery();
		
		while (resultSet->next())
		{
			
			empno = resultSet->getInt(1);  // get the first column returned by the query;
			
			ename = resultSet->getString(2);  // get the second column returned by the query
			
			hireDate = resultSet->getDate(3);  // get the third column returned by the query
			
			dateAsString="";
			
			//You cannot check for null until the data has been read
			
			if (resultSet->isNull(1))
			{
				cout << "Employee num is null... " << endl;
			}
			if (resultSet->isNull(2))
			{
				cout << "Employee name is null..." << endl;
			}
			if (resultSet->isNull(3))
			{
				cout << "Hire date is null..." << endl;
			}
			else
			{
				dateAsString=hireDate.toText(dateFormat);
			}
			cout << empno << "\t" << ename << "\t" << dateAsString << endl;
			
		}
		
		// Close ResultSet and Statement
		
		stmt->closeResultSet(resultSet);
		
		conn->terminateStatement(stmt);
		
		// Close Connection and OCCI Environment
		
		delete dbm;
		
	}
	catch (SQLException& ex)
	{
		if (dbm != NULL)
		{
			dbm->rollbackActions(ex, stmt, resultSet); // free resources and rollback transaction
		}
	}
	catch (ExoException& ex1)
	{
		cerr << "\nCaught ExoException:\n" << ex1.getExceptionText() << endl;
		exit(2);
	}
	
	return 0;
}

 

Good one

 

Thanks

 

Really cool!

 

Thanks.

 

gr8 post !

 

Thanks.

 

Getting compile-time errors like Not able to find dbmanager.h header file....
Please Help !
Thanx.

 

Hi Kush,

Sorry for the delay. Sorry, there is no need to include "dbmanager.h" by mistake i have included it.

You have to include "occi.h" like #include<occi.h> in your program.

Note one thing more this code will not work for every compiler. Either you have to use visual C++7.
Or you can use gcc comipler version 3.4.3. If you are using gcc comipler in linux then you have to download occi libraries from Oracle web site.

And you have to copy these files into your $ORACLE_HOME/lib.
If you have installed oracle client in your machine the it contains one "rdms" folder which contain one "demo" folder . From that folder you can use "demo_xe.mk" to compile your file.

If you have any further query then you can ask me.

 

Ok.

 

Hi Shabbir,
Can i edit the existing code ? Or i have to upload the new code. If it is possible to edit the code then pls tell from where i can do this.

 

Hi Shishir,
I have attached the VC++ 6.0 version connection with Oracle. It is overall the same code which you have listed out in this thread. I have also included oci.h from the Oracle Include directory. Still i am getting problems -> Please check out.

 

How about an article explain how to connect C++ to SQL ?

I using MS Visual Studio 2005.

I really noob to database as well as C++.

Thanks for your help. Your help is greatly appreciated by me and others.

 

Any guide or tutorial where i can start to learn connect C++ with msssql ?

Thanks for your help.

 

Thanks for sending

 

Thanks for your good comments.