这里又引入了一个Abstract类，抽象类
<?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) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
* @version $Id: Abstract.php 24593 2012-01-05 20:35:02Z matthew $
*/
/**
* @see Zend_Db_Adapter_Abstract
*/
require_once 'Zend/Db/Adapter/Abstract.php';
/**
* @see Zend_Db_Statement_Pdo
*/
require_once 'Zend/Db/Statement/Pdo.php';
/**
* Class for connecting to SQL databases and performing common operations using PDO.
*
* @category Zend
* @package Zend_Db
* @subpackage Adapter
* @copyright Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
*/
abstract class Zend_Db_Adapter_Pdo_Abstract extends Zend_Db_Adapter_Abstract
{
/**
* Default class name for a DB statement.
*
* @var string
*/
protected $_defaultStmtClass = 'Zend_Db_Statement_Pdo';
/**
* Creates a PDO DSN for the adapter from $this->_config settings.
*
* @return string
*/
protected function _dsn()
{
// baseline of DSN parts
$dsn = $this->_config;
// don't pass the username, password, charset, persistent and driver_options in the DSN
unset($dsn['username']);
unset($dsn['password']);
unset($dsn['options']);
unset($dsn['charset']);
unset($dsn['persistent']);
unset($dsn['driver_options']);
// use all remaining parts in the DSN
foreach ($dsn as $key => $val) {
$dsn[$key] = "$key=$val";
}
return $this->_pdoType . ':' . implode(';', $dsn);
}
/**
* Creates a PDO object and connects to the database.
*
* @return void
* @throws Zend_Db_Adapter_Exception
*/
protected function _connect()
{
// if we already have a PDO object, no need to re-connect.
if ($this->_connection) {
return;
}
// get the dsn first, because some adapters alter the $_pdoType
$dsn = $this->_dsn();
// check for PDO extension
if (!extension_loaded('pdo')) {
/**
* @see Zend_Db_Adapter_Exception
*/
require_once 'Zend/Db/Adapter/Exception.php';
throw new Zend_Db_Adapter_Exception('The PDO extension is required for this adapter but the extension is not loaded');
}
// check the PDO driver is available
if (!in_array($this->_pdoType, PDO::getAvailableDrivers())) {
/**
* @see Zend_Db_Adapter_Exception
*/
require_once 'Zend/Db/Adapter/Exception.php';
throw new Zend_Db_Adapter_Exception('The ' . $this->_pdoType . ' driver is not currently installed');
}
// create PDO connection
$q = $this->_profiler->queryStart('connect', Zend_Db_Profiler::CONNECT);
// add the persistence flag if we find it in our config array
if (isset($this->_config['persistent']) && ($this->_config['persistent'] == true)) {
$this->_config['driver_options'][PDO::ATTR_PERSISTENT] = true;
}
try {
$this->_connection = new PDO(
$dsn,
$this->_config['username'],
$this->_config['password'],
$this->_config['driver_options']
);
$this->_profiler->queryEnd($q);
// set the PDO connection to perform case-folding on array keys, or not
$this->_connection->setAttribute(PDO::ATTR_CASE, $this->_caseFolding);
// always use exceptions.
$this->_connection->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
} catch (PDOException $e) {
/**
* @see Zend_Db_Adapter_Exception
*/
require_once 'Zend/Db/Adapter/Exception.php';
throw new Zend_Db_Adapter_Exception($e->getMessage(), $e->getCode(), $e);
}
}
/**
* Test if a connection is active
*
* @return boolean
*/
public function isConnected()
{
return ((bool) ($this->_connection instanceof PDO));
}
/**
* Force the connection to close.
*
* @return void
*/
public function closeConnection()
{
$this->_connection = null;
}
/**
* Prepares an SQL statement.
*
* @param string $sql The SQL statement with placeholders.
* @param array $bind An array of data to bind to the placeholders.
* @return PDOStatement
*/
public function prepare($sql)
{
$this->_connect();
$stmtClass = $this->_defaultStmtClass;
if (!class_exists($stmtClass)) {
require_once 'Zend/Loader.php';
Zend_Loader::loadClass($stmtClass);
}
$stmt = new $stmtClass($this, $sql);
$stmt->setFetchMode($this->_fetchMode);
return $stmt;
}
/**
* Gets the last ID generated automatically by an IDENTITY/AUTOINCREMENT column.
*
* As a convention, on RDBMS brands that support sequences
* (e.g. Oracle, PostgreSQL, DB2), this method forms the name of a sequence
* from the arguments and returns the last id generated by that sequence.
* On RDBMS brands that support IDENTITY/AUTOINCREMENT columns, this method
* returns the last value generated for such a column, and the table name
* argument is disregarded.
*
* On RDBMS brands that don't support sequences, $tableName and $primaryKey
* are ignored.
*
* @param string $tableName OPTIONAL Name of table.
* @param string $primaryKey OPTIONAL Name of primary key column.
* @return string
*/
public function lastInsertId($tableName = null, $primaryKey = null)
{
$this->_connect();
return $this->_connection->lastInsertId();
}
/**
* Special handling for PDO query().
* All bind parameter names must begin with ':'
*
* @param string|Zend_Db_Select $sql The SQL statement with placeholders.
* @param array $bind An array of data to bind to the placeholders.
* @return Zend_Db_Statement_Pdo
* @throws Zend_Db_Adapter_Exception To re-throw PDOException.
*/
public function query($sql, $bind = array())
{
if (empty($bind) && $sql instanceof Zend_Db_Select) {
$bind = $sql->getBind();
}
if (is_array($bind)) {
foreach ($bind as $name => $value) {
if (!is_int($name) && !preg_match('/^:/', $name)) {
$newName = ":$name";
unset($bind[$name]);
$bind[$newName] = $value;
}
}
}
try {
return parent::query($sql, $bind);
} catch (PDOException $e) {
/**
* @see Zend_Db_Statement_Exception
*/
require_once 'Zend/Db/Statement/Exception.php';
throw new Zend_Db_Statement_Exception($e->getMessage(), $e->getCode(), $e);
}
}
/**
* Executes an SQL statement and return the number of affected rows
*
* @param mixed $sql The SQL statement with placeholders.
* May be a string or Zend_Db_Select.
* @return integer Number of rows that were modified
* or deleted by the SQL statement
*/
public function exec($sql)
{
if ($sql instanceof Zend_Db_Select) {
$sql = $sql->assemble();
}
try {
$affected = $this->getConnection()->exec($sql);
if ($affected === false) {
$errorInfo = $this->getConnection()->errorInfo();
/**
* @see Zend_Db_Adapter_Exception
*/
require_once 'Zend/Db/Adapter/Exception.php';
throw new Zend_Db_Adapter_Exception($errorInfo[2]);
}
return $affected;
} catch (PDOException $e) {
/**
* @see Zend_Db_Adapter_Exception
*/
require_once 'Zend/Db/Adapter/Exception.php';
throw new Zend_Db_Adapter_Exception($e->getMessage(), $e->getCode(), $e);
}
}
/**
* Quote a raw string.
*
* @param string $value Raw string
* @return string Quoted string
*/
protected function _quote($value)
{
if (is_int($value) || is_float($value)) {
return $value;
}
$this->_connect();
return $this->_connection->quote($value);
}
/**
* Begin a transaction.
*/
protected function _beginTransaction()
{
$this->_connect();
$this->_connection->beginTransaction();
}
/**
* Commit a transaction.
*/
protected function _commit()
{
$this->_connect();
$this->_connection->commit();
}
/**
* Roll-back a transaction.
*/
protected function _rollBack() {
$this->_connect();
$this->_connection->rollBack();
}
/**
* Set the PDO fetch mode.
*
* @todo Support FETCH_CLASS and FETCH_INTO.
*
* @param int $mode A PDO fetch mode.
* @return void
* @throws Zend_Db_Adapter_Exception
*/
public function setFetchMode($mode)
{
//check for PDO extension
if (!extension_loaded('pdo')) {
/**
* @see Zend_Db_Adapter_Exception
*/
require_once 'Zend/Db/Adapter/Exception.php';
throw new Zend_Db_Adapter_Exception('The PDO extension is required for this adapter but the extension is not loaded');
}
switch ($mode) {
case PDO::FETCH_LAZY:
case PDO::FETCH_ASSOC:
case PDO::FETCH_NUM:
case PDO::FETCH_BOTH:
case PDO::FETCH_NAMED:
case PDO::FETCH_OBJ:
$this->_fetchMode = $mode;
break;
default:
/**
* @see Zend_Db_Adapter_Exception
*/
require_once 'Zend/Db/Adapter/Exception.php';
throw new Zend_Db_Adapter_Exception("Invalid fetch mode '$mode' specified");
break;
}
}
/**
* Check if the adapter supports real SQL parameters.
*
* @param string $type 'positional' or 'named'
* @return bool
*/
public function supportsParameters($type)
{
switch ($type) {
case 'positional':
case 'named':
default:
return true;
}
}
/**
* Retrieve server version in PHP style
*
* @return string
*/
public function getServerVersion()
{
$this->_connect();
try {
$version = $this->_connection->getAttribute(PDO::ATTR_SERVER_VERSION);
} catch (PDOException $e) {
// In case of the driver doesn't support getting attributes
return null;
}
$matches = null;
if (preg_match('/((?:[0-9]{1,2}.){1,3}[0-9]{1,2})/', $version, $matches)) {
return $matches[1];
} else {
return null;
}
}
}
