lib/dml/pgsql_native_moodle_recordset.php

   1 <?php
   2
   3 // This file is part of Moodle - http://moodle.org/
   4 //
   5 // Moodle is free software: you can redistribute it and/or modify
   6 // it under the terms of the GNU General Public License as published by
   7 // the Free Software Foundation, either version 3 of the License, or
   8 // (at your option) any later version.
   9 //
  10 // Moodle is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14 //
  15 // You should have received a copy of the GNU General Public License
  16 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  17
  18
  19 /**
  20  * Native postgresql recordset.
  21  *
  22  * @package    core
  23  * @subpackage dml
  24  * @copyright  2008 Petr Skoda (http://skodak.org)
  25  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  26  */
  27
  28 defined('MOODLE_INTERNAL') || die();
  29
  30 require_once($CFG->libdir.'/dml/moodle_recordset.php');
  31
  32 /**
  33  * pgsql specific moodle recordset class
  34  */
  35 class pgsql_native_moodle_recordset extends moodle_recordset {
  36
  37     protected $result;
  38     protected $current; // current row as array
  39     protected $bytea_oid;
  40     protected $blobs = array();
  41
  42     public function __construct($result, $bytea_oid) {
  43         $this->result    = $result;
  44         $this->bytea_oid = $bytea_oid;
  45
  46         // find out if there are any blobs
  47         $numrows = pg_num_fields($result);
  48         for($i=0; $i<$numrows; $i++) {
  49             $type_oid = pg_field_type_oid($result, $i);
  50             if ($type_oid == $this->bytea_oid) {
  51                 $this->blobs[] = pg_field_name($result, $i);
  52             }
  53         }
  54
  55         $this->current = $this->fetch_next();
  56     }
  57
  58     public function __destruct() {
  59         $this->close();
  60     }
  61
  62     private function fetch_next() {
  63         $row = pg_fetch_assoc($this->result);
  64
  65         if ($this->blobs) {
  66             foreach ($this->blobs as $blob) {
  67                 $row[$blob] = $row[$blob] !== null ? pg_unescape_bytea($row[$blob]) : null;
  68             }
  69         }
  70
  71         return $row;
  72     }
  73
  74     public function current() {
  75         return (object)$this->current;
  76     }
  77
  78     public function key() {
  79     /// return first column value as key
  80         if (!$this->current) {
  81             return false;
  82         }
  83         $key = reset($this->current);
  84         return $key;
  85     }
  86
  87     public function next() {
  88         $this->current = $this->fetch_next();
  89     }
  90
  91     public function valid() {
  92         return !empty($this->current);
  93     }
  94
  95     public function close() {
  96         if ($this->result) {
  97             pg_free_result($this->result);
  98             $this->result  = null;
  99         }
 100         $this->current = null;
 101         $this->blobs   = null;
 102     }
 103 }