text: <?php
  /**
   * Zend Framework
   *
   * LICENSE
   *
   * This source file is subject to the new BSD license that is bundled
   * with this package in the file LICENSE.txt.
   * It is also available through the world-wide-web at this URL:
   * http://framework.zend.com/license/new-bsd
   * If you did not receive a copy of the license and are unable to
   * obtain it through the world-wide-web, please send an email
   * to license@zend.com so we can send you a copy immediately.
   *
   * @category   Zend
   * @package    Zend_Db
   * @subpackage Adapter
   * @copyright  Copyright (c) 2005-2011 Zend Technologies USA Inc. (http://www.zend.com)
   * @license    http://framework.zend.com/license/new-bsd     New BSD License
   * @version    $Id: Mysql.php 23986 2011-05-03 20:10:42Z ralph $
   */
  
  
  /**
   * @see Zend_Db_Adapter_Pdo_Abstract
   */
  require_once 'include/Zend/Db/Adapter/Pdo/Abstract.php';
  
  
  /**
   * Class for connecting to MySQL databases and performing common operations.
   *
   * @category   Zend
   * @package    Zend_Db
   * @subpackage Adapter
   * @copyright  Copyright (c) 2005-2011 Zend Technologies USA Inc. (http://www.zend.com)
   * @license    http://framework.zend.com/license/new-bsd     New BSD License
   */
  class Zend_Db_Adapter_Pdo_Mysql extends Zend_Db_Adapter_Pdo_Abstract
  {
  
      /**
       * PDO type.
       *
       * @var string
       */
      protected $_pdoType = 'mysql';
  
      /**
       * Keys are UPPERCASE SQL datatypes or the constants
       * Zend_Db::INT_TYPE, Zend_Db::BIGINT_TYPE, or Zend_Db::FLOAT_TYPE.
       *
       * Values are:
       * 0 = 32-bit integer
       * 1 = 64-bit integer
       * 2 = float or decimal
       *
       * @var array Associative array of datatypes to values 0, 1, or 2.
       */
      protected $_numericDataTypes = array(
          Zend_Db::INT_TYPE    => Zend_Db::INT_TYPE,
          Zend_Db::BIGINT_TYPE => Zend_Db::BIGINT_TYPE,
          Zend_Db::FLOAT_TYPE  => Zend_Db::FLOAT_TYPE,
          'INT'                => Zend_Db::INT_TYPE,
          'INTEGER'            => Zend_Db::INT_TYPE,
          'MEDIUMINT'          => Zend_Db::INT_TYPE,
          'SMALLINT'           => Zend_Db::INT_TYPE,
          'TINYINT'            => Zend_Db::INT_TYPE,
          'BIGINT'             => Zend_Db::BIGINT_TYPE,
          'SERIAL'             => Zend_Db::BIGINT_TYPE,
          'DEC'                => Zend_Db::FLOAT_TYPE,
          'DECIMAL'            => Zend_Db::FLOAT_TYPE,
          'DOUBLE'             => Zend_Db::FLOAT_TYPE,
          'DOUBLE PRECISION'   => Zend_Db::FLOAT_TYPE,
          'FIXED'              => Zend_Db::FLOAT_TYPE,
          'FLOAT'              => Zend_Db::FLOAT_TYPE
      );
  
      /**
       * Override _dsn() and ensure that charset is incorporated in mysql
       * @see Zend_Db_Adapter_Pdo_Abstract::_dsn()
       */
      protected function _dsn()
      {
          $dsn = parent::_dsn();
          if (isset($this->_config['charset'])) {
              $dsn .= ';charset=' . $this->_config['charset'];
          }
          return $dsn;
      }
      
      /**
       * Creates a PDO object and connects to the database.
       *
       * @return void
       * @throws Zend_Db_Adapter_Exception
       */
      protected function _connect()
      {
          if ($this->_connection) {
              return;
          }
  
          if (!empty($this->_config['charset'])) {
              $initCommand = "SET NAMES '" . $this->_config['charset'] . "'";
              $this->_config['driver_options'][1002] = $initCommand; // 1002 = PDO::MYSQL_ATTR_INIT_COMMAND
          }
  
          parent::_connect();
      }
  
      /**
       * @return string
       */
      public function getQuoteIdentifierSymbol()
      {
          return "`";
      }
  
      /**
       * Returns a list of the tables in the database.
       *
       * @return array
       */
      public function listTables()
      {
          return $this->fetchCol('SHOW TABLES');
      }
  
      /**
       * Returns the column descriptions for a table.
       *
       * The return value is an associative array keyed by the column name,
       * as returned by the RDBMS.
       *
       * The value of each array element is an associative array
       * with the following keys:
       *
       * SCHEMA_NAME      => string; name of database or schema
       * TABLE_NAME       => string;
       * COLUMN_NAME      => string; column name
       * COLUMN_POSITION  => number; ordinal position of column in table
       * DATA_TYPE        => string; SQL datatype name of column
       * DEFAULT          => string; default expression of column, null if none
       * NULLABLE         => boolean; true if column can have nulls
       * LENGTH           => number; length of CHAR/VARCHAR
       * SCALE            => number; scale of NUMERIC/DECIMAL
       * PRECISION        => number; precision of NUMERIC/DECIMAL
       * UNSIGNED         => boolean; unsigned property of an integer type
       * PRIMARY          => boolean; true if column is part of the primary key
       * PRIMARY_POSITION => integer; position of column in primary key
       * IDENTITY         => integer; true if column is auto-generated with unique values
       *
       * @param string $tableName
       * @param string $schemaName OPTIONAL
       * @return array
       */
      public function describeTable($tableName, $schemaName = null)
      {
          // @todo  use INFORMATION_SCHEMA someday when MySQL's
          // implementation has reasonably good performance and
          // the version with this improvement is in wide use.
  
          if ($schemaName) {
              $sql = 'DESCRIBE ' . $this->quoteIdentifier("$schemaName.$tableName", true);
          } else {
              $sql = 'DESCRIBE ' . $this->quoteIdentifier($tableName, true);
          }
          $stmt = $this->query($sql);
  
          // Use FETCH_NUM so we are not dependent on the CASE attribute of the PDO connection
          $result = $stmt->fetchAll(Zend_Db::FETCH_NUM);
  
          $field   = 0;
          $type    = 1;
          $null    = 2;
          $key     = 3;
          $default = 4;
          $extra   = 5;
  
          $desc = array();
          $i = 1;
          $p = 1;
          foreach ($result as $row) {
              list($length, $scale, $precision, $unsigned, $primary, $primaryPosition, $identity)
                  = array(null, null, null, null, false, null, false);
              if (preg_match('/unsigned/', $row[$type])) {
                  $unsigned = true;
              }
              if (preg_match('/^((?:var)?char)\((\d+)\)/', $row[$type], $matches)) {
                  $row[$type] = $matches[1];
                  $length = $matches[2];
              } else if (preg_match('/^decimal\((\d+),(\d+)\)/', $row[$type], $matches)) {
                  $row[$type] = 'decimal';
                  $precision = $matches[1];
                  $scale = $matches[2];
              } else if (preg_match('/^float\((\d+),(\d+)\)/', $row[$type], $matches)) {
                  $row[$type] = 'float';
                  $precision = $matches[1];
                  $scale = $matches[2];
              } else if (preg_match('/^((?:big|medium|small|tiny)?int)\((\d+)\)/', $row[$type], $matches)) {
                  $row[$type] = $matches[1];
                  // The optional argument of a MySQL int type is not precision
                  // or length; it is only a hint for display width.
              }
              if (strtoupper($row[$key]) == 'PRI') {
                  $primary = true;
                  $primaryPosition = $p;
                  if ($row[$extra] == 'auto_increment') {
                      $identity = true;
                  } else {
                      $identity = false;
                  }
                  ++$p;
              }
              $desc[$this->foldCase($row[$field])] = array(
                  'SCHEMA_NAME'      => null, // @todo
                  'TABLE_NAME'       => $this->foldCase($tableName),
                  'COLUMN_NAME'      => $this->foldCase($row[$field]),
                  'COLUMN_POSITION'  => $i,
                  'DATA_TYPE'        => $row[$type],
                  'DEFAULT'          => $row[$default],
                  'NULLABLE'         => (bool) ($row[$null] == 'YES'),
                  'LENGTH'           => $length,
                  'SCALE'            => $scale,
                  'PRECISION'        => $precision,
                  'UNSIGNED'         => $unsigned,
                  'PRIMARY'          => $primary,
                  'PRIMARY_POSITION' => $primaryPosition,
                  'IDENTITY'         => $identity
              );
              ++$i;
          }
          return $desc;
      }
  
      /**
       * Adds an adapter-specific LIMIT clause to the SELECT statement.
       *
       * @param  string $sql
       * @param  integer $count
       * @param  integer $offset OPTIONAL
       * @throws Zend_Db_Adapter_Exception
       * @return string
       */
       public function limit($sql, $count, $offset = 0)
       {
          $count = intval($count);
          if ($count <= 0) {
              /** @see Zend_Db_Adapter_Exception */
              require_once 'include/Zend/Db/Adapter/Exception.php';
              throw new Zend_Db_Adapter_Exception("LIMIT argument count=$count is not valid");
          }
  
          $offset = intval($offset);
          if ($offset < 0) {
              /** @see Zend_Db_Adapter_Exception */
              require_once 'include/Zend/Db/Adapter/Exception.php';
              throw new Zend_Db_Adapter_Exception("LIMIT argument offset=$offset is not valid");
          }
  
          $sql .= " LIMIT $count";
          if ($offset > 0) {
              $sql .= " OFFSET $offset";
          }
  
          return $sql;
      }
  
  }
  