PHP用来操作MySQL数据库的类

LAMP或者LNMP架构，PHP和MySQL数据库的联动，尤其是频繁操作不是很方便(貌似所有的语言都差不多-_-!!)。通用的做法就是将平常用到的操作查询、更新、插入、删除等操作封装到一个类里面，可以方便对数据库进行操作。下面是我项目中用到的类，参考了不少的资料。
用配置文件的方法可以灵活的配置不同的数据库连接，配置文件mysqldb.conf.php。

<?php 
$db_config["hostname"] = "xxx.xxx.xxx.xxx:x3306"; 
//服务器地址,使用非标准端口需要指定端口 
$db_config["username"] = "xxxxxx"; 
//数据库用户名 
$db_config["password"] = "************"; 
//数据库密码 
$db_config["database"] = "xxxxxx"; 
//数据库名称 
$db_config["charset"] = "utf8";
//数据库编码 
$db_config["pconnect"] = 1;
//开启持久连接 
$db_config["log"] = 1;
//开启日志 
$db_config["logfilepath"] = '/opt/log/mysqldb.php.log';

mysqlDB类用来操作数据库的代码。

<?php 
Class mysqlDB { 
  private $link_id; 
  private $handle; 
  private $is_log; 
  private $time; 
  
  //构造函数 
  public function __construct() { 
    $this->time = $this->microtime_float(); 
    require_once("/xxx/xxxx/conf/mysqldb.config.php"); 
    $this->connect($db_config["hostname"], $db_config["username"], $db_config["password"], $db_config["database"], $db_config["pconnect"]); 
    $this->is_log = $db_config["log"]; 
    if($this->is_log){ 
      $handle = fopen("/opt/log/mysqldb.php.log", "a+"); 
      $this->handle=$handle; 
    } 
  } 
  
  //连接数据库 
  public function connect($dbhost, $dbuser, $dbpw, $dbname, $pconnect = 0,$charset='utf8') { 
    if( $pconnect==0 ) { 
      $this->link_id = @mysql_connect($dbhost, $dbuser, $dbpw, true); 
      if(!$this->link_id){ 
        $this->halt("数据库连接失败"); 
      } 
    } else { 
      $this->link_id = @mysql_pconnect($dbhost, $dbuser, $dbpw); 
      if(!$this->link_id){ 
        $this->halt("数据库持久连接失败"); 
      } 
    } 
    if(!@mysql_select_db($dbname,$this->link_id)) { 
      $this->halt('数据库选择失败'); 
    } 
    @mysql_query("set names ".$charset); 
  } 
  
  //查询 
  public function query($sql) { 
    $this->write_log("查询 ".$sql); 
    $query = mysql_query($sql); 
    if(!$query) $this->halt('Query Error: ' . $sql); 
    return $query; 
  } 
  
  //获取查询条件的一条记录（MYSQL_ASSOC，MYSQL_NUM，MYSQL_BOTH） 
  public function get_one($sql,$result_type = MYSQL_ASSOC) { 
    $query = $this->query($sql); 
    $rt = mysql_fetch_array($query,$result_type); 
    $this->write_log("获取了一条记录 ".$sql); 
    return $rt; 
  } 
  
  //获取查询条件的所有记录 
  public function get_all($sql,$result_type = MYSQL_ASSOC) { 
    $query = $this->query($sql); 
    $i = 0; 
    $rt = array(); 
    while($row = mysql_fetch_array($query,$result_type)) { 
      $rt[$i]=$row; 
      $i++; 
    } 
    $this->write_log("获取了全部记录 ".$sql); 
    return $rt; 
  } 
  
  //插入一条记录 
  public function insert($table,$dataArray) { 
    $field = ""; 
    $value = ""; 
    if( !is_array($dataArray) || count($dataArray)<=0) { 
      $this->halt('没有要插入的数据'); 
      return false; 
    } 
    while(list($key,$val)=each($dataArray)) { 
      $field .="$key,"; 
      $value .="'$val',"; 
    } 
    $field = substr( $field,0,-1); 
    $value = substr( $value,0,-1); 
    $sql = "insert into $table($field) values($value)"; 
    $this->write_log("插入一条记录 ".$sql); 
    if(!$this->query($sql)) return false; 
    return true; 
  } 
  
  //更新一条记录 
  public function update( $table,$dataArray,$condition="") { 
    if( !is_array($dataArray) || count($dataArray)<=0) { 
      $this->halt('没有要更新的数据'); 
      return false; 
    } 
    $value = ""; 
    while( list($key,$val) = each($dataArray)) 
    $value .= "$key = '$val',"; 
    $value .= substr( $value,0,-1); 
    $sql = "update $table set $value where 1=1 and $condition"; 
    $this->write_log("更新一条记录 ".$sql); 
    if(!$this->query($sql)) return false; 
    return true; 
  } 
  
  //删除 
  public function delete( $table,$condition="") { 
    if( empty($condition) ) { 
      $this->halt('没有设置删除的条件'); 
      return false; 
    } 
    $sql = "delete from $table where 1=1 and $condition"; 
    $this->write_log("删除 ".$sql); 
    if(!$this->query($sql)) return false; 
    return true; 
  } 
  
  //返回结果集 
  public function fetch_array($query, $result_type = MYSQL_ASSOC){ 
    $this->write_log("返回结果集"); 
    return mysql_fetch_array($query, $result_type); 
  } 
  
  //获取记录条数 
  public function num_rows($results) { 
    if(!is_bool($results)) { 
      $num = mysql_num_rows($results); 
      $this->write_log("获取的记录条数为".$num); 
      return $num; 
    } else { 
      return 0; 
    } 
  } 
  
  //释放结果集 
  public function free_result() { 
    $void = func_get_args(); 
    foreach($void as $query) { 
      if(is_resource($query) && get_resource_type($query) === 'mysql result') { 
        return mysql_free_result($query); 
      } 
    } 
    $this->write_log("释放结果集"); 
  } 
  
  //获取最后插入的id 
  public function insert_id() { 
    $id = mysql_insert_id($this->link_id); 
    $this->write_log("最后插入的id为".$id); 
    return $id; 
  } 
  
  //关闭数据库连接 
  protected function close() { 
    $this->write_log("已关闭数据库连接"); 
    return @mysql_close($this->link_id); 
  } 
  
  //错误提示 
  private function halt($msg='') { 
    $msg .= "\\r\\n".mysql_error(); 
    $this->write_log($msg); 
    die($msg); 
  } 
  
  //析构函数 
  public function __destruct() { 
    $this->free_result(); 
    $use_time = ($this-> microtime_float())-($this->time); 
    $this->write_log("完成整个查询任务,所用时间为".$use_time); 
    if($this->is_log){ 
      fclose($this->handle); 
    } 
  } 
  
  //写入日志文件 
  public function write_log($msg=''){ 
    if($this->is_log){ 
      $text = date("Y-m-d H:i:s")." ".$msg."\\r\\n"; fwrite($this->handle,$text); 
    } 
  } 
  
  //获取毫秒数 
  public function microtime_float() { 
    list($usec, $sec) = explode(" ", microtime()); 
    return ((float)$usec + (float)$sec); 
  } 
}

这个mysqlDB类经过运维平台验证。比较稳定，用法也比较简单。

<?php 
include_once(xxxx/mysqldb.class.php); 
$mysql = new mysqlDB; 
$select_one = $mysql->get_one($sql,MYSQL_ASSOC);#三种模式按需所选,函数默认为MYSQL_ASSOC模式