Setting Firebird Database Engine in PHP

<?php

    session_start(); //You can enable error reporting by setting value to 1

    error_reporting(0);

 //echo session_id();

    $_SESSION['currsession'] = session_id();

    if(isset($_SESSION['result_session'])){

        $endsession = $_SESSION['result_session'];

    }

    if($endsession == $_SESSION['currsession']){

        header('location:grades.php');

    }
   
    include_once("DBConnect/constants.php");
    include_once("DBConnect/DBInstance.php");
   
    DBInstance::setDBEngine(DBASE_ENGINE);
    DBInstance::setDBase(YOUR_DATABASE_NAME_HERE);
   
   
    $dbInstance = DBInstance::getInstance();
   
    $trans = ibase_trans(IBASE_DEFAULT,$dbInstance);
   
    $positionList= array();
    //if(isset($_POST["issubmit"])){
        //validation here.
       
        try{
               
                   
            $query = "Your Query Here";
           
            $pstmt = ibase_prepare($trans,$query);
            $result = ibase_execute($pstmt);
            if(!$result){
                throw new Exception(ibase_errmsg(),ibase_errcode());
            }
           
            while($row = ibase_fetch_object($result)){
           
                $positionList[]= array(
                    "position"=>$row->POSITION,
                    "description"=>$row->DESC
                );
            }
        //print_r($positionList);
       
            ibase_commit($trans);
        }catch(Exception $e){
            echo "No data dump to system database, Transaction has been rolled back.";
            echo $e->getMessage();
            ibase_rollback($trans);
           
        }
    //}
   
?>

Note: If you are using Linux Web Server make sure that you have a correct Systax in PHP.