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Differences Between: [Versions 400 and 401] [Versions 400 and 402] [Versions 400 and 403]

   1  <?php
   2  // This file is part of Moodle - http://moodle.org/
   3  //
   4  // Moodle is free software: you can redistribute it and/or modify
   5  // it under the terms of the GNU General Public License as published by
   6  // the Free Software Foundation, either version 2 of the License, or
   7  // (at your option) any later version.
   8  //
   9  // Moodle is distributed in the hope that it will be useful,
  10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  // GNU General Public License for more details.
  13  //
  14  // You should have received a copy of the GNU General Public License
  15  // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16  
  17  /**
  18   * sqlsrv specific recordset.
  19   *
  20   * @package    core_dml
  21   * @copyright  2009 onwards Eloy Lafuente (stronk7) {@link http://stronk7.com}
  22   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v2 or later
  23   */
  24  
  25  defined('MOODLE_INTERNAL') || die();
  26  
  27  require_once (__DIR__.'/moodle_recordset.php');
  28  
  29  class sqlsrv_native_moodle_recordset extends moodle_recordset {
  30  
  31      protected $rsrc;
  32      protected $current;
  33  
  34      /** @var array recordset buffer */
  35      protected $buffer = null;
  36  
  37      /** @var sqlsrv_native_moodle_database */
  38      protected $db;
  39  
  40      public function __construct($rsrc, sqlsrv_native_moodle_database $db) {
  41          $this->rsrc    = $rsrc;
  42          $this->current = $this->fetch_next();
  43          $this->db      = $db;
  44      }
  45  
  46      /**
  47       * Inform existing open recordsets that transaction
  48       * is starting, this works around MARS problem described
  49       * in MDL-37734.
  50       */
  51      public function transaction_starts() {
  52          if ($this->buffer !== null) {
  53              $this->unregister();
  54              return;
  55          }
  56          if (!$this->rsrc) {
  57              $this->unregister();
  58              return;
  59          }
  60          // This might eat memory pretty quickly...
  61          raise_memory_limit('2G');
  62          $this->buffer = array();
  63  
  64          while($next = $this->fetch_next()) {
  65              $this->buffer[] = $next;
  66          }
  67      }
  68  
  69      /**
  70       * Unregister recordset from the global list of open recordsets.
  71       */
  72      private function unregister() {
  73          if ($this->db) {
  74              $this->db->recordset_closed($this);
  75              $this->db = null;
  76          }
  77      }
  78  
  79      public function __destruct() {
  80          $this->close();
  81      }
  82  
  83      private function fetch_next() {
  84          if (!$this->rsrc) {
  85              return false;
  86          }
  87          if (!$row = sqlsrv_fetch_array($this->rsrc, SQLSRV_FETCH_ASSOC)) {
  88              sqlsrv_free_stmt($this->rsrc);
  89              $this->rsrc = null;
  90              $this->unregister();
  91              return false;
  92          }
  93  
  94          unset($row['sqlsrvrownumber']);
  95          $row = array_change_key_case($row, CASE_LOWER);
  96          // Moodle expects everything from DB as strings.
  97          foreach ($row as $k=>$v) {
  98              if (is_null($v)) {
  99                  continue;
 100              }
 101              if (!is_string($v)) {
 102                  $row[$k] = (string)$v;
 103              }
 104          }
 105          return $row;
 106      }
 107  
 108      public function current() {
 109          return (object)$this->current;
 110      }
 111  
 112      public function key() {
 113          // return first column value as key
 114          if (!$this->current) {
 115              return false;
 116          }
 117          $key = reset($this->current);
 118          return $key;
 119      }
 120  
 121      public function next() {
 122          if ($this->buffer === null) {
 123              $this->current = $this->fetch_next();
 124          } else {
 125              $this->current = array_shift($this->buffer);
 126          }
 127      }
 128  
 129      public function valid() {
 130          return !empty($this->current);
 131      }
 132  
 133      public function close() {
 134          if ($this->rsrc) {
 135              sqlsrv_free_stmt($this->rsrc);
 136              $this->rsrc  = null;
 137          }
 138          $this->current = null;
 139          $this->buffer  = null;
 140          $this->unregister();
 141      }
 142  }