PHP实例：ZendFramework框架实现连接两个或多个数据库的方法

 <db>
    <adapter>PDO_MSSQL</adapter>
  <config>
      <host>localhost</host>
      <port>1433</port>
      <username>sa</username>
      <password>123456</password>
      <dbname>edudb</dbname>
      <pdoType>sqlsrv</pdoType>
    </config>
  </db>
  <!-- 测试多数据库 -->
  <db2>
    <adapter>PDO_MSSQL</adapter>
      <config>
      <host>localhost</host>
      <port>1433</port>
      <username>sa</username>
      <password>123456</password>
      <dbname>test</dbname>
      <pdoType>sqlsrv</pdoType>
    </config>
  </db2>

//配置数据库连接
$db_config = $web_config->db->config->toArray(); 
//var_dump($db_config);
$db = Zend_Db::factory($web_config->db->adapter, $db_config); 
//var_dump($db);
//exit;
//$db->query('set NAMES utf8');
//$db->getProfiler()->setEnabled(false); 
Zend_Db_Table::setDefaultAdapter($db); 

$db = &$this->getAdapter();

function init() {
    $web_config = $this->getCfg();
    $this->db2_config = $web_config->db2->config->toArray(); 
    //var_dump($this->db_config);
    $this->db = Zend_Db::factory($web_config->db2->adapter, $this->db2_config); 
    Zend_Db_Table::setDefaultAdapter($this->db); 
}
public function returnDb(){
    return $this->db;
}

$db = &$this->getAdapter();

$this->db

<?php
class dao_dao2 extends Zend_Db_Table {
  protected $cfg_; 
  function init() {
    $web_config = $this->getCfg();
    $this->db2_config = $web_config->db2->config->toArray(); 
    //var_dump($this->db_config);
    $this->db = Zend_Db::factory($web_config->db2->adapter, $this->db2_config); 
    Zend_Db_Table::setDefaultAdapter($this->db); 
  }
  public function returnDb(){
    return $this->db;
  }
  public function getData($table,$where = false, $order = 'id ASC', $pagesize = false, $offset = false, $count = false, $from = false, $join = false, $group = false) {
    //$this->db = &$this->getAdapter();
    $select = $this->db->select();
    if ($where && is_array($where)) {
      foreach ($where as $key => $val) {
        //print_r($where);
        if($val['type']==1){
          $select->where($key, $this->convert2gbk($val['val']));
        }else{
          $select->orwhere($key, $this->convert2gbk($val['val']));
        }
      } 
    }
    if (!$from)
      $from = '*';
    //echo $select."<br/>";
    if ($pagesize) {
      $select->limit($pagesize, $offset);
    }
    //echo $select."<br/>";
    if (is_array($order)) {
      foreach ($order as $value) {
        $select->order($value);
      }
    } else {
      $select->order($order);
    }
    //echo $select."<br/>";
    $select->from($table, $count ? "COUNT(".$table.".id)" : $from);
    if (is_array($group)) {
      foreach ($group as $key => $val) {
        $select->group($val);
      }
      if ($count) {
        $result = $this->db->fetchAll($select);
        //echo $select."<br/>";
        return $result;
      }
    } else {
      if ($count) {
        $result = $this->db->fetchOne($select);
        //echo $select."<br/>";
        return $result;
      }
    }
    if (is_array($join)) {
      foreach ($join as $key => $val) {
        //$select->join($key, $val[0], $val[1]);
        $select->joinleft($key, $val[0], $val[1]);
      }
    }
    //echo $select."<br/>";
    //echo $select;exit;
    $result = $this->db->fetchAll($select);
    foreach ($result as $key => $value) {
      foreach ($value as $key2 => $value2) {
        $result[$key][$key2] = $this->convert2utf8($value2);
      }
    }
    return $result;
  }
  /**
   * 向表中插入数据
   * array $adata 数据
   * string $table 表名
   * int $insterid 是否需要返回插入ID
   * @return true or false or int
   */
   // @bianding 2013.11.04 更改了pdo中mssql.php的lastInsertId()函数
   // @bianding 2013.11.04 经测试 mssql.php中的lastInsertId()函数中的SELECT两种方式都行
  function SaveData($adata, $table, $insterid = 0, $aLog = false) {
    //$this->db = &$this->getAdapter();
    foreach ($adata as $key => $value) {
      $adata[$key] = $this->convert2gbk($value);
    }
    if ($this->db->insert($table, $adata)) {
      //var_dump($this->db->getProfiler());
      $insertedID = $this->db->lastInsertId();      
      if ($insterid) {
        return $insertedID;
      } else {
        return TRUE;
      }
    } else {
      return false;
    }
  }
  /**
   * 删除表中数据
   * 
   * @param string $table 表名
   * @param string $where 'id ='.$id 条件
   * @return true or false
   */
  function DelData($table, $where, $aLog = false) {
    //$this->db = & $this->getAdapter();
    if ($this->db->delete($table, $where)) {
      return TRUE;
    } else {
      return FALSE;
    }
  }
  /**
   * 更新表中数据
   *
   * @param string $table
   * @param array $adata
   * @param string $where 'id ='.$id
   * @return true or false
   */
  function UpdateData($table, $adata, $cond, $aLog = false) {
    //$this->db = & $this->getAdapter();
    foreach ($adata as $key => $value) {
      $adata[$key] = $this->convert2gbk($value);
    }
    if ($this->db->update($table, $adata, $cond)) {
      return TRUE;
    } else {
      return false;
    }
  }
  public function clearTable($table) {
    //$this->db = &$this->getAdapter();
    $result = $this->db->query('TRUNCATE TABLE ' . $table);
  }
  public function executeSql($strSql) {
    //$this->db = &$this->getAdapter();
    $result = $this->db->query($strSql);
  }
  function convert2utf8($string)
  {
    $config = $this->getCfg();
    $pdoType = $config->db->config->pdoType;
    if($pdoType == 'dblib'){
      return iconv("gbk","utf-8",$string);
    }elseif($pdoType == 'sqlsrv'){
      //$encode = mb_detect_encoding($string, array('UTF-8',"GB2312",'GBK','BIG5')); 
      //echo $encode;
      return mb_convert_encoding($string,"UTF-8","UTF-8");
      //return $string;
    }
  }
  function convert2gbk($string)
  {
    $config = $this->getCfg();
    $pdoType = $config->db->config->pdoType;
    if($pdoType == 'dblib'){
      return iconv("utf-8","gbk",$string);
    }elseif($pdoType == 'sqlsrv'){
      //$encode = mb_detect_encoding($string, array('UTF-8',"GB2312",'GBK','BIG5')); 
      //echo $encode; 
      return mb_convert_encoding($string,"UTF-8","UTF-8");
      //return $string;
    }
  }
  protected function &getCfg() {
    if ($this->cfg_ === null) {
      $registry = Zend_Registry::getInstance();
      $this->cfg_ = $registry->get('web_config');
    }
    return $this->cfg_;
  } 
}