[Sommaire] [Imprimer]

   1  <?php
   2  // $Id: database.mysql.inc,v 1.66.2.1 2007/01/22 02:20:50 unconed Exp $
   3  
   4  /**
   5   * @file
   6   * Database interface code for MySQL database servers.
   7   */
   8  
   9  /**
  10   * @ingroup database
  11   * @{
  12   */
  13  
  14  
  15  /**
  16   * Report database status.
  17   */
  18  function db_status_report($phase) {
  19    $t = get_t();
  20  
  21    $version = db_version();
  22  
  23    $form['mysql'] = array(
  24      'title' => $t('MySQL database'),
  25      'value' => ($phase == 'runtime') ? l($version, 'admin/logs/status/sql') : $version,
  26    );
  27  
  28    if (version_compare($version, DRUPAL_MINIMUM_MYSQL) < 0) {
  29      $form['mysql']['severity'] = REQUIREMENT_ERROR;
  30      $form['mysql']['description'] = $t('Your MySQL Server is too old. Drupal requires at least MySQL %version.', array('%version' => DRUPAL_MINIMUM_MYSQL));
  31    }
  32  
  33    return $form;
  34  }
  35  
  36  /**
  37   * Returns the version of the database server currently in use.
  38   *
  39   * @return Database server version
  40   */
  41  function db_version() {
  42    list($version) = explode('-', mysql_get_server_info());
  43    return $version;
  44  }
  45  
  46  /**
  47   * Initialize a database connection.
  48   *
  49   * Note that you can change the mysql_connect() call to mysql_pconnect() if you
  50   * want to use persistent connections. This is not recommended on shared hosts,
  51   * and might require additional database/webserver tuning. It can increase
  52   * performance, however, when the overhead to connect to your database is high
  53   * (e.g. your database and web server live on different machines).
  54   */
  55  function db_connect($url) {
  56    $url = parse_url($url);
  57  
  58    // Check if MySQL support is present in PHP
  59    if (!function_exists('mysql_connect')) {
  60      // Redirect to installer if using default DB credentials
  61      if ($url['user'] == 'username' && $url['pass'] == 'password') {
  62        include_once  'includes/install.inc';
  63        install_goto('install.php');
  64      }
  65      drupal_maintenance_theme();
  66      drupal_set_title('PHP MySQL support not enabled');
  67      print theme('maintenance_page', '<p>We were unable to use the MySQL database because the MySQL extension for PHP is not installed. Check your <code>PHP.ini</code> to see how you can enable it.</p>
  68  <p>For more help, see the <a href="http://drupal.org/node/258">Installation and upgrading handbook</a>. If you are unsure what these terms mean you should probably contact your hosting provider.</p>');
  69      exit;
  70    }
  71  
  72    // Decode url-encoded information in the db connection string
  73    $url['user'] = urldecode($url['user']);
  74    // Test if database url has a password.
  75    if(isset($url['pass'])) {
  76      $url['pass'] = urldecode($url['pass']);
  77    }
  78    else {
  79      $url['pass'] = '';
  80    }
  81    $url['host'] = urldecode($url['host']);
  82    $url['path'] = urldecode($url['path']);
  83  
  84    // Allow for non-standard MySQL port.
  85    if (isset($url['port'])) {
  86       $url['host'] = $url['host'] .':'. $url['port'];
  87    }
  88  
  89    // - TRUE makes mysql_connect() always open a new link, even if
  90    //   mysql_connect() was called before with the same parameters.
  91    //   This is important if you are using two databases on the same
  92    //   server.
  93    // - 2 means CLIENT_FOUND_ROWS: return the number of found
  94    //   (matched) rows, not the number of affected rows.
  95    $connection = @mysql_connect($url['host'], $url['user'], $url['pass'], TRUE, 2);
  96    if (!$connection) {
  97      // Redirect to installer if using default DB credentials
  98      if ($url['user'] == 'username' && $url['pass'] == 'password') {
  99        include_once  'includes/install.inc';
 100        install_goto('install.php');
 101      }
 102  
 103      // Show error screen otherwise
 104      drupal_maintenance_theme();
 105      drupal_set_header('HTTP/1.1 503 Service Unavailable');
 106      drupal_set_title('Unable to connect to database server');
 107      print theme('maintenance_page', '<p>If you still have to install Drupal, proceed to the <a href="'. base_path() .'install.php">installation page</a>.</p>
 108  <p>If you have already finished installed Drupal, this either means that the username and password information in your <code>settings.php</code> file is incorrect or that we can\'t connect to the MySQL database server. This could mean your hosting provider\'s database server is down.</p>
 109  <p>The MySQL error was: '. theme('placeholder', mysql_error()) .'.</p>
 110  <p>Currently, the username is '. theme('placeholder', $url['user']) .' and the database server is '. theme('placeholder', $url['host']) .'.</p>
 111  <ul>
 112    <li>Are you sure you have the correct username and password?</li>
 113    <li>Are you sure that you have typed the correct hostname?</li>
 114    <li>Are you sure that the database server is running?</li>
 115  </ul>
 116  <p>For more help, see the <a href="http://drupal.org/node/258">Installation and upgrading handbook</a>. If you are unsure what these terms mean you should probably contact your hosting provider.</p>');
 117      exit;
 118    }
 119  
 120    if (!mysql_select_db(substr($url['path'], 1))) {
 121      drupal_maintenance_theme();
 122      drupal_set_title('Unable to select database');
 123      print theme('maintenance_page', '<p>We were able to connect to the MySQL database server (which means your username and password are okay) but not able to select the database.</p>
 124  <p>The MySQL error was: '. theme('placeholder', mysql_error($connection)) .'.</p>
 125  <p>Currently, the database is '. theme('placeholder', substr($url['path'], 1)) .'. The username is '. theme('placeholder', $url['user']) .' and the database server is '. theme('placeholder', $url['host']) .'.</p>
 126  <ul>
 127    <li>Are you sure you have the correct database name?</li>
 128    <li>Are you sure the database exists?</li>
 129    <li>Are you sure the username has permission to access the database?</li>
 130  </ul>
 131  <p>For more help, see the <a href="http://drupal.org/node/258">Installation and upgrading handbook</a>. If you are unsure what these terms mean you should probably contact your hosting provider.</p>');
 132      exit;
 133    }
 134  
 135    /* On MySQL 4.1 and later, force UTF-8 */
 136    if (version_compare(mysql_get_server_info(), '4.1.0', '>=')) {
 137      mysql_query('SET NAMES "utf8"', $connection);
 138    }
 139    return $connection;
 140  }
 141  
 142  /**
 143   * Helper function for db_query().
 144   */
 145  function _db_query($query, $debug = 0) {
 146    global $active_db, $queries;
 147  
 148    if (variable_get('dev_query', 0)) {
 149      list($usec, $sec) = explode(' ', microtime());
 150      $timer = (float)$usec + (float)$sec;
 151    }
 152  
 153    $result = mysql_query($query, $active_db);
 154  
 155    if (variable_get('dev_query', 0)) {
 156      $bt = debug_backtrace();
 157      $query = $bt[2]['function'] . "\n" . $query;
 158      list($usec, $sec) = explode(' ', microtime());
 159      $stop = (float)$usec + (float)$sec;
 160      $diff = $stop - $timer;
 161      $queries[] = array($query, $diff);
 162    }
 163  
 164    if ($debug) {
 165      print '<p>query: '. $query .'<br />error:'. mysql_error($active_db) .'</p>';
 166    }
 167  
 168    if (!mysql_errno($active_db)) {
 169      return $result;
 170    }
 171    else {
 172      trigger_error(check_plain(mysql_error($active_db) ."\nquery: ". $query), E_USER_WARNING);
 173      return FALSE;
 174    }
 175  }
 176  
 177  /**
 178   * Fetch one result row from the previous query as an object.
 179   *
 180   * @param $result
 181   *   A database query result resource, as returned from db_query().
 182   * @return
 183   *   An object representing the next row of the result. The attributes of this
 184   *   object are the table fields selected by the query.
 185   */
 186  function db_fetch_object($result) {
 187    if ($result) {
 188      return mysql_fetch_object($result);
 189    }
 190  }
 191  
 192  /**
 193   * Fetch one result row from the previous query as an array.
 194   *
 195   * @param $result
 196   *   A database query result resource, as returned from db_query().
 197   * @return
 198   *   An associative array representing the next row of the result. The keys of
 199   *   this object are the names of the table fields selected by the query, and
 200   *   the values are the field values for this result row.
 201   */
 202  function db_fetch_array($result) {
 203    if ($result) {
 204      return mysql_fetch_array($result, MYSQL_ASSOC);
 205    }
 206  }
 207  
 208  /**
 209   * Determine how many result rows were found by the preceding query.
 210   *
 211   * @param $result
 212   *   A database query result resource, as returned from db_query().
 213   * @return
 214   *   The number of result rows.
 215   */
 216  function db_num_rows($result) {
 217    if ($result) {
 218      return mysql_num_rows($result);
 219    }
 220  }
 221  
 222  /**
 223   * Return an individual result field from the previous query.
 224   *
 225   * Only use this function if exactly one field is being selected; otherwise,
 226   * use db_fetch_object() or db_fetch_array().
 227   *
 228   * @param $result
 229   *   A database query result resource, as returned from db_query().
 230   * @param $row
 231   *   The index of the row whose result is needed.
 232   * @return
 233   *   The resulting field or FALSE.
 234   */
 235  function db_result($result, $row = 0) {
 236    if ($result && mysql_num_rows($result) > $row) {
 237      return mysql_result($result, $row);
 238    }
 239    return FALSE;
 240  }
 241  
 242  /**
 243   * Determine whether the previous query caused an error.
 244   */
 245  function db_error() {
 246    global $active_db;
 247    return mysql_errno($active_db);
 248  }
 249  
 250  /**
 251   * Return a new unique ID in the given sequence.
 252   *
 253   * For compatibility reasons, Drupal does not use auto-numbered fields in its
 254   * database tables. Instead, this function is used to return a new unique ID
 255   * of the type requested. If necessary, a new sequence with the given name
 256   * will be created.
 257   *
 258   * Note that the table name should be in curly brackets to preserve compatibility
 259   * with table prefixes. For example, db_next_id('{node}_nid');
 260   */
 261  function db_next_id($name) {
 262    $name = db_prefix_tables($name);
 263    db_query('LOCK TABLES {sequences} WRITE');
 264    $id = db_result(db_query("SELECT id FROM {sequences} WHERE name = '%s'", $name)) + 1;
 265    db_query("REPLACE INTO {sequences} VALUES ('%s', %d)", $name, $id);
 266    db_query('UNLOCK TABLES');
 267  
 268    return $id;
 269  }
 270  
 271  /**
 272   * Determine the number of rows changed by the preceding query.
 273   */
 274  function db_affected_rows() {
 275    global $active_db;
 276    return mysql_affected_rows($active_db);
 277  }
 278  
 279  /**
 280   * Runs a limited-range query in the active database.
 281   *
 282   * Use this as a substitute for db_query() when a subset of the query is to be
 283   * returned.
 284   * User-supplied arguments to the query should be passed in as separate parameters
 285   * so that they can be properly escaped to avoid SQL injection attacks.
 286   *
 287   * @param $query
 288   *   A string containing an SQL query.
 289   * @param ...
 290   *   A variable number of arguments which are substituted into the query
 291   *   using printf() syntax. The query arguments can be enclosed in one
 292   *   array instead.
 293   *   Valid %-modifiers are: %s, %d, %f, %b (binary data, do not enclose
 294   *   in '') and %%.
 295   *
 296   *   NOTE: using this syntax will cast NULL and FALSE values to decimal 0,
 297   *   and TRUE values to decimal 1.
 298   *
 299   * @param $from
 300   *   The first result row to return.
 301   * @param $count
 302   *   The maximum number of result rows to return.
 303   * @return
 304   *   A database query result resource, or FALSE if the query was not executed
 305   *   correctly.
 306   */
 307  function db_query_range($query) {
 308    $args = func_get_args();
 309    $count = array_pop($args);
 310    $from = array_pop($args);
 311    array_shift($args);
 312  
 313    $query = db_prefix_tables($query);
 314    if (isset($args[0]) and is_array($args[0])) { // 'All arguments in one array' syntax
 315      $args = $args[0];
 316    }
 317    _db_query_callback($args, TRUE);
 318    $query = preg_replace_callback(DB_QUERY_REGEXP, '_db_query_callback', $query);
 319    $query .= ' LIMIT '. (int)$from .', '. (int)$count;
 320    return _db_query($query);
 321  }
 322  
 323  /**
 324   * Runs a SELECT query and stores its results in a temporary table.
 325   *
 326   * Use this as a substitute for db_query() when the results need to stored
 327   * in a temporary table. Temporary tables exist for the duration of the page
 328   * request.
 329   * User-supplied arguments to the query should be passed in as separate parameters
 330   * so that they can be properly escaped to avoid SQL injection attacks.
 331   *
 332   * Note that if you need to know how many results were returned, you should do
 333   * a SELECT COUNT(*) on the temporary table afterwards. db_num_rows() and
 334   * db_affected_rows() do not give consistent result across different database
 335   * types in this case.
 336   *
 337   * @param $query
 338   *   A string containing a normal SELECT SQL query.
 339   * @param ...
 340   *   A variable number of arguments which are substituted into the query
 341   *   using printf() syntax. The query arguments can be enclosed in one
 342   *   array instead.
 343   *   Valid %-modifiers are: %s, %d, %f, %b (binary data, do not enclose
 344   *   in '') and %%.
 345   *
 346   *   NOTE: using this syntax will cast NULL and FALSE values to decimal 0,
 347   *   and TRUE values to decimal 1.
 348   *
 349   * @param $table
 350   *   The name of the temporary table to select into. This name will not be
 351   *   prefixed as there is no risk of collision.
 352   * @return
 353   *   A database query result resource, or FALSE if the query was not executed
 354   *   correctly.
 355   */
 356  function db_query_temporary($query) {
 357    $args = func_get_args();
 358    $tablename = array_pop($args);
 359    array_shift($args);
 360  
 361    $query = preg_replace('/^SELECT/i', 'CREATE TEMPORARY TABLE '. $tablename .' SELECT', db_prefix_tables($query));
 362    if (isset($args[0]) and is_array($args[0])) { // 'All arguments in one array' syntax
 363      $args = $args[0];
 364    }
 365    _db_query_callback($args, TRUE);
 366    $query = preg_replace_callback(DB_QUERY_REGEXP, '_db_query_callback', $query);
 367    return _db_query($query);
 368  }
 369  
 370  /**
 371   * Returns a properly formatted Binary Large OBject value.
 372   *
 373   * @param $data
 374   *   Data to encode.
 375   * @return
 376   *  Encoded data.
 377   */
 378  function db_encode_blob($data) {
 379    global $active_db;
 380    return "'" . mysql_real_escape_string($data, $active_db) . "'";
 381  }
 382  
 383  /**
 384   * Returns text from a Binary Large Object value.
 385   *
 386   * @param $data
 387   *   Data to decode.
 388   * @return
 389   *  Decoded data.
 390   */
 391  function db_decode_blob($data) {
 392    return $data;
 393  }
 394  
 395  /**
 396   * Prepare user input for use in a database query, preventing SQL injection attacks.
 397   */
 398  function db_escape_string($text) {
 399    global $active_db;
 400    return mysql_real_escape_string($text, $active_db);
 401  }
 402  
 403  /**
 404   * Lock a table.
 405   */
 406  function db_lock_table($table) {
 407    db_query('LOCK TABLES {'. db_escape_table($table) .'} WRITE');
 408  }
 409  
 410  /**
 411   * Unlock all locked tables.
 412   */
 413  function db_unlock_tables() {
 414    db_query('UNLOCK TABLES');
 415  }
 416  
 417  /**
 418   * Check if a table exists.
 419   */
 420  function db_table_exists($table) {
 421    return db_num_rows(db_query("SHOW TABLES LIKE '{" . db_escape_table($table) . "}'"));
 422  }
 423  
 424  /**
 425   * Wraps the given table.field entry with a DISTINCT(). The wrapper is added to
 426   * the SELECT list entry of the given query and the resulting query is returned.
 427   * This function only applies the wrapper if a DISTINCT doesn't already exist in
 428   * the query.
 429   *
 430   * @param $table Table containing the field to set as DISTINCT
 431   * @param $field Field to set as DISTINCT
 432   * @param $query Query to apply the wrapper to
 433   * @return SQL query with the DISTINCT wrapper surrounding the given table.field.
 434   */
 435  function db_distinct_field($table, $field, $query) {
 436    $field_to_select = 'DISTINCT('. $table .'.'. $field .')';
 437    // (?<!text) is a negative look-behind (no need to rewrite queries that already use DISTINCT).
 438    return preg_replace('/(SELECT.*)(?:'. $table .'\.|\s)(?<!DISTINCT\()(?<!DISTINCT\('. $table .'\.)'. $field .'(.*FROM )/AUsi', '\1 '. $field_to_select .'\2', $query);
 439  }
 440  
 441  /**
 442   * @} End of "ingroup database".
 443   */
 444  
 445