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PDO数据库操作类
网络 2013/9/25 17:34:21PHP代码
<?php
/**
* 功能:数据库操作类
* 作者:phpox
* 日期:Tue Aug 14 08:46:27 CST 2007
*/
defined('PHPOX') or die(header("HTTP/1.1 403 Not Forbidden"));
class include_database
{
private static $instance;
public $dsn;
public $dbuser;
public $dbpass;
public $sth;
public $dbh;
private function __construct()
{
$this->dsn = 'mysql:host='.DB_HOST.';port='.DB_PORT.';dbname='.DB_NAME;
$this->dbuser = DB_USER;
$this->dbpass = DB_PASS;
$this->connect();
$this->dbh->query('SET NAMES '.DB_CHARSET);
}
public static function getInstance()
{
if (self::$instance === null)
{
self::$instance = new include_database();
}
return self::$instance;
}
//连接数据库
private function connect()
{
try
{
$this->dbh = new PDO($this->dsn,$this->dbuser,$this->dbpass);
}
catch (PDOException $e)
{
exit('连接失败:'.$e->getMessage());
}
}
//获取数据表里的字段
public function getFields($table)
{
$this->sth = $this->dbh->query("DESCRIBE $table");
$this->getPDOError();
$this->sth->setFetchMode(PDO::FETCH_ASSOC);
$result = $this->sth->fetchAll();
$this->sth = null;
return $result;
}
//获取要操作的数据
private function getCode($table,$args)
{
$allTables = require_once(DOCUMENT_ROOT.'/cache/tables.php');
if (!is_array($allTables[$table]))
{
exit('表名错误或未更新缓存!');
}
$tables = array_flip($allTables[$table]);
$unarr = array_diff_key($args,$tables);
if (is_array($unarr))
{
foreach ($unarr as $k => $v)
{
unset($args[$k]);
}
}
$code = '';
if (is_array($args))
{
foreach ($args as $k => $v)
{
if ($v == '')
{
continue;
}
$code .= "`$k`='$v',";
}
}
$code = substr($code,0,-1);
return $code;
}
//插入数据
public function insert($table,$args,$debug = null)
{
$sql = "INSERT INTO `$table` SET ";
$code = $this->getCode($table,$args);
$sql .= $code;
if ($debug)echo $sql;
if ($this->dbh->exec($sql))
{
$this->getPDOError();
return $this->dbh->lastInsertId();
}
return false;
}
//查询数据
public function fetch($table,$condition = '',$sort = '',$limit = '',$field = '*',$debug = false)
{
$sql = "SELECT {$field} FROM `{$table}`";
if (false !== ($con = $this->getCondition($condition)))
{
$sql .= $con;
}
if ($sort != '')
{
$sql .= " ORDER BY $sort";
}
if ($limit != ''){
$sql .= " LIMIT $limit";
}
if ($debug)echo $sql;
$this->sth = $this->dbh->query($sql);
$this->getPDOError();
$this->sth->setFetchMode(PDO::FETCH_ASSOC);
$result = $this->sth->fetchAll();
$this->sth = null;
return $result;
}
//查询数据
public function fetchOne($table,$condition = null,$field = '*',$debug = false)
{
$sql = "SELECT {$field} FROM `{$table}`";
if (false !== ($con = $this->getCondition($condition)))
{
$sql .= $con;
}
if ($debug)echo $sql;
$this->sth = $this->dbh->query($sql);
$this->getPDOError();
$this->sth->setFetchMode(PDO::FETCH_ASSOC);
$result = $this->sth->fetch();
$this->sth = null;
return $result;
}
//获取查询条件
public function getCondition($condition='')
{
if ($condition != '')
{
$con = ' WHERE';
if (is_array($condition))
{
$i = 0;
foreach ($condition as $k => $v)
{
if ($i != 0){
$con .= " AND $k = '$v'";
}else {
$con .= " $k = '$v'";
}
$i++;
}
}elseif (is_string($condition))
{
$con .= " $condition";
}else {
return false;
}
return $con;
}
return false;
}
//获取记录总数
public function counts($table,$condition = '',$debug = false)
{
$sql = "SELECT COUNT(*) AS num FROM `$table`";
if (false !== ($con = $this->getCondition($condition)))
{
$sql .= $con;
}
if ($debug) echo $sql;
$count = $this->dbh->query($sql);
$this->getPDOError();
return $count->fetchColumn();
}
//按SQL语句查询
public function doSql($sql,$model='many',$debug = false)
{
if ($debug)echo $sql;
$this->sth = $this->dbh->query($sql);
$this->getPDOError();
$this->sth->setFetchMode(PDO::FETCH_ASSOC);
if ($model == 'many')
{
$result = $this->sth->fetchAll();
}else {
$result = $this->sth->fetch();
}
$this->sth = null;
return $result;
}
//修改数据
public function update($table,$args,$condition,$debug = null)
{
$code = $this->getCode($table,$args);
$sql = "UPDATE `$table` SET ";
$sql .= $code;
if (false !== ($con = $this->getCondition($condition)))
{
$sql .= $con;
}
if ($debug)echo $sql;
if (($rows = $this->dbh->exec($sql)) > 0)
{
$this->getPDOError();
return $rows;
}
return false;
}
//字段递增
public function increase($table,$condition,$field,$debug=false)
{
$sql = "UPDATE `$table` SET $field = $field + 1";
if (false !== ($con = $this->getCondition($condition))){
$sql .= $con;
}
if ($debug)echo $sql;
if (($rows = $this->dbh->exec($sql)) > 0){
$this->getPDOError();
return $rows;
}
return false;
}
//删除记录
public function del($table,$condition,$debug = false)
{
$sql = "DELETE FROM `$table`";
if (false !== ($con = $this->getCondition($condition)))
{
$sql .= $con;
}else {
exit('条件错误!');
}
if ($debug)echo $sql;
if (($rows = $this->dbh->exec($sql)) > 0)
{
$this->getPDOError();
return $rows;
}else {
return false;
}
}
/**
* 执行无返回值的SQL查询
*
*/
public function execute($sql)
{
$this->dbh->exec($sql);
$this->getPDOError();
}
/**
* 捕获PDO错误信息
*/
private function getPDOError()
{
if ($this->dbh->errorCode() != '00000')
{
$error = $this->dbh->errorInfo();
exit($error[2]);
}
}
//关闭数据连接
public function __destruct()
{
$this->dbh = null;
}
}阅读(5445) 分享(0)
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