/**
 * Class BaseMethod
 * �ӿڶ������
 * @auther Ӧ��
 */
class BaseMethod
{
	// raw��������ָ���ֶ��Ƿ�ԭʼ���ݴ��䣬Ϊtrue���Բ�����ʽ���ݸ�pdo
	const PROPERTYNAME_RAW   = 'raw';
	// type���������ƶ��ֶ���������
	const PROPERTYNAME_TYPE  = 'type';
	// value���������ֶε�ֵ
	const PROPERTYNAME_VALUE = 'value';

	// type���Կ�ѡֵ
	const TYPENAME_STRING    = 'string'; // �ַ�������
	const TYPENAME_NUMBER    = 'number'; // ��ֵ����
	const TYPENAME_DATE      = 'date'; // ��������
	const TYPENAME_TIMESTAMP = 'timestamp'; // ʱ�������
	const TYPENAME_LOB       = 'lob'; // ����������
	const TYPENAME_RAW       = 'raw'; // Դ��������


	// where �ֶ�Ҫ�õ�������Ԫ����
	const CONDITION_NAMES    = 'conditions'; // �����ֶ�
	const CONDITION_VALUE    = 'values'; // ����ֵ


	// ��ѯ�ֶ�Ҫ�õ�������Ԫ����
	const FIELDNAME_FIELD    = 'field'; // Դ�ֶ���
	const FIELDNAME_ALIAS    = 'alias'; // ���ֶ�����������Alias


	// sql����õ�������Ԫ����
	const COMMAND_LINE       = 'commandline';
	const COMMAND_VARS       = 'commandvars';

	/**
	 * @note ������
	 * @var int
	 * @auther Ӧ��
	 */
	protected $ErrorCode;

	/**
	 * @note ������Ϣ
	 * @var string|mixed
	 * @auther Ӧ��
	 */
	protected $ErrorInfo;

	/**
	 * @var DatabaseHelper
	 */
	protected $Database;
	
	//private $ReferenceCharacter;
	private $RefCharLeft;
	private $RefCharRight;

	/**
	 * BaseMethod constructor.
	 */
	public function __construct()
	{
		if (0 == strcasecmp('MYSQL', DATABASE_TYPE))
		{
			$p = array(
				PARAMETERNAME_HOSTNAME => DB_HOSTNAME,
				PARAMETERNAME_HOSTPORT => DB_HOSTPORT,
				PARAMETERNAME_DATABASE => DB_DATABASE,
				PARAMETERNAME_USERNAME => DB_USERNAME,
				PARAMETERNAME_PASSWORD => DB_PASSWORD,
				PARAMETERNAME_CHARSET => DB_CHARSET,
			);

			$this->Database = new MYSQLHelper();
			$this->Database->FetchStyle = PDO::FETCH_ASSOC;
			if (!$this->Database->Connect($p))
			{
				$this->ErrorCode = $this->Database->GetErrorCode();
				$this->ErrorInfo = $this->Database->GetErrorInfo();

				$this->Database = null;
			}

			$this->RefCharLeft = '`';
			$this->RefCharRight = '`';
		}
		elseif (0 == strcasecmp('SQLSRV', DATABASE_TYPE))
		{
			$p = array(
				PARAMETERNAME_HOSTNAME => DB_HOSTNAME,
				PARAMETERNAME_HOSTPORT => DB_HOSTPORT,
				PARAMETERNAME_DATABASE => DB_DATABASE,
				PARAMETERNAME_USERNAME => DB_USERNAME,
				PARAMETERNAME_PASSWORD => DB_PASSWORD,
			);

			$this->Database = new SQLSRVHelper();
			$this->Database->FetchStyle = PDO::FETCH_ASSOC;
			if (!$this->Database->Connect($p))
			{
				$this->ErrorCode = $this->Database->GetErrorCode();
				$this->ErrorInfo = $this->Database->GetErrorInfo();

				$this->Database = null;
			}

			$this->RefCharLeft = '[';
			$this->RefCharRight = ']';
		}
		elseif (0 == strcasecmp('ORACLE', DATABASE_TYPE))
		{
			$p = array(
				PARAMETERNAME_HOSTNAME => DB_HOSTNAME,
				PARAMETERNAME_HOSTPORT => DB_HOSTPORT,
				PARAMETERNAME_SERVICE => DB_DATABASE,
				PARAMETERNAME_USERNAME => DB_USERNAME,
				PARAMETERNAME_PASSWORD => DB_PASSWORD,
			);

			$this->Database = new ORACLEHelper();
			$this->Database->FetchStyle = PDO::FETCH_ASSOC;
			if (!$this->Database->Connect($p))
			{
				$this->ErrorCode = $this->Database->GetErrorCode();
				$this->ErrorInfo = $this->Database->GetErrorInfo();

				$this->Database = null;
			}

			$this->RefCharLeft = '';
			$this->RefCharRight = '';
		}
		else
		{
			$this->Database = null;
			$this->ErrorCode = ERRORCODE_BADPARAMETER;
			$this->ErrorInfo = sprintf(ERRORINFO_BADPARAMETER, 'dbtype', DATABASE_TYPE);
		}
	}

	/**
	 * BaseMethod destructor
	 */
	public function __destruct()
	{
		$this->Database = null;
	}


	/**
	 * @note pdo�������ݣ��з��ؽ������
	 * @param mixed
	 * @return mixed|null
	 */
	protected function PDO_Request()
	{
		if (null == $this->Database)
		{
			return null;
		}

		$return = call_user_func_array(array($this->Database, 'Request'), func_get_args());
		$this->ErrorCode = $this->Database->GetErrorCode();
		$this->ErrorInfo = $this->Database->GetErrorInfo();
		return $return;
	}

	/**
	 * @note pdoִ����䣨�޷��ؽ������
	 * @param mixed
	 * @return mixed|null
	 */
	protected function PDO_Execute()
	{
		if (null == $this->Database)
		{
			return null;
		}
		$return = call_user_func_array(array($this->Database, 'Execute'), func_get_args());
		$this->ErrorCode = $this->Database->GetErrorCode();
		$this->ErrorInfo = $this->Database->GetErrorInfo();
		return $return;
	}

	/**
	 * @note ���һ��ִ�в���󣬲������Զ����
	 * @param string $name
	 * @return bool|null|string
	 */
	protected function PDO_LastInsertId($name = null)
	{
		if (null == $this->Database)
		{
			return null;
		}
		else
		{
			return $this->Database->LastInsertId($name);
		}
	}

	/**
	 * @note ����һ������
	 * @return bool|null
	 */
	protected function PDO_BeginTransaction()
	{
		if (null == $this->Database)
		{
			return null;
		}
		else
		{
			return $this->Database->BeginTransaction();
		}
	}

	/**
	 * @note �ύһ������
	 * @return bool|null
	 */
	protected function PDO_Commit()
	{
		if (null == $this->Database)
		{
			return null;
		}
		else
		{
			return $this->Database->Commit();
		}
	}

	/**
	 * @note �ع�һ������
	 * @return bool|null
	 */
	protected function PDO_Rollback()
	{
		if (null == $this->Database)
		{
			return null;
		}
		else
		{
			return $this->Database->Rollback();
		}
	}


	protected function GetRandString($prefix = '')
	{
		return (empty($prefix) ? '' : $prefix) . rand(1000, 9999);
	}


	/**
	 * @note ����ʶ�������޶���
	 * @param string $Identifiers Ҫ����ı�ʶ��
	 * @param bool $Quoted �Ƿ��Ǵ�������
	 * @param string $SpecialChar Ҫ�ر���(����)���ַ�
	 */
	protected function GetIdentifiers($Identifiers, $Quoted = false, $SpecialChar = null)
	{
		if (is_null($Identifiers) || '' == $Identifiers)
		{
			return '';
		}
		elseif ($Quoted)
		{
			$Length = mb_strlen($Identifiers, USEDCHARSET);
			if ("'" == mb_substr($Identifiers, 0, 1, USEDCHARSET))
			{
				$Length--;
				$Identifiers = mb_substr($Identifiers, 1, $Length, USEDCHARSET);
			}
			if ("'" == mb_substr($Identifiers, $Length - 1, 1, USEDCHARSET))
			{
				$Length--;
				$Identifiers = mb_substr($Identifiers, 0, $Length, USEDCHARSET);
			}

			return "'" . str_replace("'", "''", $Identifiers) . "'";
		}
		elseif (!empty($SpecialChar) && mb_strstr($Identifiers, $SpecialChar, false, USEDCHARSET))
		{
			$Identifiers = str_replace($SpecialChar, $this->RefCharLeft . $SpecialChar . $this->RefCharRight, $Identifiers);
			return $this->RefCharLeft . $Identifiers . $this->RefCharRight;
		}
		else
		{
			return $this->RefCharLeft . $Identifiers . $this->RefCharRight;
		}
	}


	/**
	 * @note ��ȡsql��������
	 * @param array|mixed $ands ���ֶ���=�ֶ�ֵ��
	 * @param array|mixed $ors ���ֶ���=�ֶ�ֵ��
	 * @return array
	 */
	private function GetWheres($ands = null, $ors = null)
	{
		if (is_object($ands))
		{
			$ands = (array)$ands;
		}
		if (is_object($ors))
		{
			$ors = (array)$ors;
		}

		$result = array(
			Self::CONDITION_NAMES => '',
			Self::CONDITION_VALUE => array(),
		);

		if (!empty($ands) || !empty($ors))
		{
			// and����
			$_ands = '1 = 1';
			if (is_array($ands))
			{
				foreach ($ands as $k => $v)
				{
					if (null === $v)
					{
						continue;
					}

					if (is_object($v))
					{
						$v = (array)$v;
					}

					// 2016-12-17��չ���ֶ�ֵ����ָ��raw���ԣ����rawΪtrue���Բ�����ʽ���ݡ�
					$raw = isset($v[Self::PROPERTYNAME_RAW]) ? $v[Self::PROPERTYNAME_RAW] : false;
					$type = isset($v[Self::PROPERTYNAME_TYPE]) ? $v[Self::PROPERTYNAME_TYPE] : Self::TYPENAME_RAW;
					// ֵ
					if (is_array($v))
					{
						$v = isset($v[Self::PROPERTYNAME_VALUE]) ? $v[Self::PROPERTYNAME_VALUE] : null;
					}

					if ($raw)
					{
						switch ($type)
						{
							case Self::TYPENAME_DATE:
							{
								if (is_numeric($v))
								{
									$_ands .= sprintf(' and %s = %s', $this->GetIdentifiers($k), $this->Timestamp2DatetimeFormat($v));
								}
								else
								{
									$_ands .= sprintf(' and %s = %s', $this->GetIdentifiers($k), $this->String2DatetimeFormat($v));
								}
								break;
							}

							case Self::TYPENAME_TIMESTAMP:
							{
								if (is_numeric($v))
								{
									$_ands .= sprintf(' and %s = %s', $this->GetIdentifiers($k), $v);
								}
								else
								{
									$_ands .= sprintf(' and %s = %s', $this->GetIdentifiers($k), $this->Datetime2TimestampFormat($v));
								}

								break;
							}

							case Self::TYPENAME_STRING:
							{
								$_ands .= sprintf(' and %s = %s', $this->GetIdentifiers($k), $this->GetIdentifiers($v, true));
								break;
							}

							default:
							{
								$_ands .= sprintf(' and %s = %s', $this->GetIdentifiers($k), $v);
								break;
							}
						}
					}
					else
					{
						switch ($type)
						{
							case Self::TYPENAME_DATE:
							{
								if (is_numeric($v))
								{
									$_ands .= sprintf(' and %s = %s', $this->GetIdentifiers($k), $this->Timestamp2DatetimeFormat('?'));
								}
								else
								{
									$_ands .= sprintf(' and %s = %s', $this->GetIdentifiers($k), $this->String2DatetimeFormat('?', false));
								}
								break;
							}

							case Self::TYPENAME_TIMESTAMP:
							{
								if (is_numeric($v))
								{
									$_ands .= sprintf(' and %s = ?', $this->GetIdentifiers($k));
								}
								else
								{
									$_ands .= sprintf(' and %s = %s', $this->GetIdentifiers($k), $this->Datetime2TimestampFormat('?', false));
								}

								break;
							}

							default:
							{
								$_ands .= sprintf(' and %s = ?', $this->GetIdentifiers($k));
								break;
							}
						}

						array_push($result[Self::CONDITION_VALUE], $v);
					}
				}
			}
			else
			{
				$_ands = empty($ands) ? '' : $ands;
			}

			// or ����
			$_ors = '';
			if (is_array($ors))
			{
				$_ors = '1 = 0';
				foreach ($ors as $k => $v)
				{
					if (null === $v)
					{
						continue;
					}

					if (is_object($v))
					{
						$v = (array)$v;
					}

					// 2016-12-17��չ���ֶ�ֵ����ָ��raw���ԣ����rawΪtrue���Բ�����ʽ���ݡ�
					$raw = isset($v[Self::PROPERTYNAME_RAW]) ? $v[Self::PROPERTYNAME_RAW] : false;
					$type = isset($v[Self::PROPERTYNAME_TYPE]) ? $v[Self::PROPERTYNAME_TYPE] : Self::TYPENAME_RAW;
					// ֵ
					if (is_array($v))
					{
						$v = isset($v[Self::PROPERTYNAME_VALUE]) ? $v[Self::PROPERTYNAME_VALUE] : null;
					}

					if ($raw)
					{
						switch ($type)
						{
							case Self::TYPENAME_DATE:
							{
								if (is_numeric($v))
								{
									$_ors .= sprintf(' or %s = %s', $this->GetIdentifiers($k), $this->Timestamp2DatetimeFormat($v));
								}
								else
								{
									$_ors .= sprintf(' or %s = %s', $this->GetIdentifiers($k), $this->String2DatetimeFormat($v));
								}
								break;
							}

							case Self::TYPENAME_TIMESTAMP:
							{
								if (is_numeric($v))
								{
									$_ors .= sprintf(' or %s = %s', $this->GetIdentifiers($k), $v);
								}
								else
								{
									$_ors .= sprintf(' or %s = %s', $this->GetIdentifiers($k), $this->Datetime2TimestampFormat($v));
								}

								break;
							}

							case Self::TYPENAME_STRING:
							{
								$_ors .= sprintf(' or %s = %s', $this->GetIdentifiers($k), $this->GetIdentifiers($v, true));
								break;
							}

							default:
							{
								$_ors .= sprintf(' or %s = %s', $this->GetIdentifiers($k), $v);
								break;
							}
						}
					}
					else
					{
						switch ($type)
						{
							case Self::TYPENAME_DATE:
							{
								if (is_numeric($v))
								{
									$_ors .= sprintf(' or %s = %s', $this->GetIdentifiers($k), $this->Timestamp2DatetimeFormat('?'));
								}
								else
								{
									$_ors .= sprintf(' or %s = %s', $this->GetIdentifiers($k), $this->String2DatetimeFormat('?', false));
								}
								break;
							}

							case Self::TYPENAME_TIMESTAMP:
							{
								if (is_numeric($v))
								{
									$_ors .= sprintf(' or %s = ?', $this->GetIdentifiers($k));
								}
								else
								{
									$_ors .= sprintf(' or %s = %s', $this->GetIdentifiers($k), $this->Datetime2TimestampFormat('?', false));
								}

								break;
							}

							default:
							{
								$_ors .= sprintf(' or %s = ?', $this->GetIdentifiers($k));
								break;
							}
						}

						array_push($result[Self::CONDITION_VALUE], $v);
					}
				}
			}
			else
			{
				$_ors = empty($ors) ? '' : $ors;
			}

			if (empty($_ands) && empty($_ors))
			{
				$result[Self::CONDITION_NAMES] = '';
			}
			elseif (empty($_ands))
			{
				$result[Self::CONDITION_NAMES] = $_ors;
			}
			elseif (empty($_ors))
			{
				$result[Self::CONDITION_NAMES] = $_ands;
			}
			else
			{
				$result[Self::CONDITION_NAMES] = '(' . $_ands . ') and (' . $_ors . ')';
			}
		}

		return $result;
	}


	/**
	 * @note ��ȡsql����������Ϣ
	 * @param array|mixed $orders ���ֶ���=�ֶ�ֵ��
	 * @return string
	 */
	private function GetOrders($orders = null)
	{
		if (empty($orders))
		{
			return '';
		}

		if (is_object($orders))
			$orders = (array)$orders;

		if (is_array($orders))
		{
			$os = '';
			foreach ($orders as $k => $v)
			{
				$os .= sprintf(' %s %s,', $this->GetIdentifiers($k, false, '.'), empty($v) ? 'asc' : $v);
			}

			$os = mb_substr($os, 0, mb_strlen($os, USEDCHARSET) - 1, USEDCHARSET);
		}
		else
		{
			$os = $orders;
		}

		return $os;
	}


	/**
	 * 2017-03-31 ����
	 * @note ��ȡsql���ķ�����Ϣ
	 * @param array|mixed $groups ���ֶ���=�ֶ�ֵ��
	 * @return string
	 */
	private function GetGroups($groups = null)
	{
		if (empty($groups))
		{
			return '';
		}

		if (is_object($groups))
			$groups = (array)$groups;

		if (is_array($groups))
		{
			$gs = '';
			foreach ($groups as $k => $v)
			{
				$gs .= sprintf(' %s,', $this->GetIdentifiers($v, false, '.'));
			}

			$gs = mb_substr($gs, 0, mb_strlen($gs, USEDCHARSET) - 1, USEDCHARSET);
		}
		else
		{
			$gs = $groups;
		}

		return $gs;
	}


	/**
	 * @note ��ȡsql��ѯ���ı���Ϣ��2017-03-03�������÷������ڴ������������
	 * @param array|mixed $tables
	 * @return string
	 */
	private function GetSelectTables($tables = null)
	{
		if (is_object($tables))
		{
			$tables = (array)$tables;
		}

		if (is_array($tables))
		{
			$return = '';

			foreach($tables as $k => $v)
			{
				// ����
				if (!empty($k) && !is_numeric($k))
				{
					$return .= ',' . $this->GetIdentifiers($v, false, '.') . ' ' . $this->GetIdentifiers($k);
				}
				else
				{
					$return .= ',' . $this->GetIdentifiers($v, false, '.');
				}
			}

			$sublen = mb_strlen(',', USEDCHARSET);
			$return = mb_substr($return, $sublen, mb_strlen($return, USEDCHARSET) - $sublen, USEDCHARSET);

			return $return;
		}
		else
		{
			return $this->GetIdentifiers($tables, false, ',');
		}
	}


	/**
	 * @note ��ȡsql��ѯ�����ֶ���Ϣ
	 * @param array|mixed $fields������=>ԭ�ֶ�/���ʽ��
	 * @return array
	 */
	private function GetSelectFields($fields = null)
	{
		$fs = array(
			Self::FIELDNAME_FIELD => '',
			Self::FIELDNAME_ALIAS => '',
		);

		if (is_object($fields))
		{
			$fields = (array)$fields;
		}

		if (is_array($fields))
		{
			foreach($fields as $k => $v)
			{
				if (is_object($v) || is_array($v))
				{
					$arr = $this->GetSelectFields($v);
					$fs[Self::FIELDNAME_FIELD] .= ', ' . $arr[Self::FIELDNAME_FIELD];
					$fs[Self::FIELDNAME_ALIAS] .= ', ' . $arr[Self::FIELDNAME_ALIAS];
					continue;
				}
				elseif (null === $v)
				{
					continue;
				}

				// 2017-03-03�����Ӷ������а���.�Ĵ���
				$nv = mb_strstr($v, '.', false, USEDCHARSET);
				if (!empty($nv)) // ����.�����������޶�����
				{
					$v = $this->GetIdentifiers($v, false, '.');

					$sublen = mb_strlen('.', USEDCHARSET);
					$nv = $this->GetIdentifiers(mb_substr($nv, $sublen, mb_strlen($nv, USEDCHARSET) - $sublen, USEDCHARSET));
				}
				else
				{
					$v = $this->GetIdentifiers($v);
					$nv = $v;
				}

				// ����
				if (!empty($k) && !is_numeric($k))
				{
					$k = $this->GetIdentifiers($k);

					$fs[Self::FIELDNAME_FIELD] .= ', ' . $v . ' ' . $k;
					$fs[Self::FIELDNAME_ALIAS] .= ', ' . $k;
				}
				else
				{
					$fs[Self::FIELDNAME_FIELD] .= ', ' . $v;
					$fs[Self::FIELDNAME_ALIAS] .= ', ' . $nv;
				}
			}

			$sublen = mb_strlen(', ', USEDCHARSET);

			if (!empty($fs[Self::FIELDNAME_FIELD]))
			{
				$fs[Self::FIELDNAME_FIELD] = mb_substr($fs[Self::FIELDNAME_FIELD], $sublen, mb_strlen($fs[Self::FIELDNAME_FIELD], USEDCHARSET) - $sublen, USEDCHARSET);
			}

			if (!empty($fs[Self::FIELDNAME_ALIAS]))
			{
				$fs[Self::FIELDNAME_ALIAS] = mb_substr($fs[Self::FIELDNAME_ALIAS], $sublen, mb_strlen($fs[Self::FIELDNAME_ALIAS], USEDCHARSET) - $sublen, USEDCHARSET);
			}
		}
		else
		{
			$fs[Self::FIELDNAME_FIELD] = $fields;
			$fs[Self::FIELDNAME_ALIAS] = $fields;
		}

		return $fs;
	}


	/**
	 * 2016-12-17��չ���ֶ�ֵ����ָ��raw���ԣ����rawΪtrue���Բ�����ʽ���ݡ�
	 * @note ִ��һ���������
	 * @param string $tablename ����
	 * @param array $fields �ֶΣ��ֶ���=�ֶ�ֵ�� 
	 * @param bool $replace �Ƿ񸲸Dz���
	 * @param array|string $refer ����Ǹ���ʱ, �ο����ֶ�
	 * @return bool|mixed|null
	 */
	protected function PDO_Insert($tablename, $fields, $replace = false, $refer = null)
	{
		if (null == $this->Database)
		{
			return false;
		}
		if (is_object($fields))
		{
			$fields = (array)$fields;
		}

		$ks = '';
		$kss = '';
		$kst = '';
		$ksv = '';
		$ps = '';
		$ss = '';
		$vs = array();
		foreach ($fields as $k => $v)
		{
			if (null === $v)
			{
				continue;
			}

			if (is_object($v))
			{
				$v = (array)$v;
			}

			// 2016-12-17��չ���ֶ�ֵ����ָ��raw���ԣ����rawΪtrue���Բ�����ʽ���ݡ�
			$raw = isset($v[Self::PROPERTYNAME_RAW]) ? $v[Self::PROPERTYNAME_RAW] : false;
			$type = isset($v[Self::PROPERTYNAME_TYPE]) ? $v[Self::PROPERTYNAME_TYPE] : Self::TYPENAME_RAW;
			// ֵ
			if (is_array($v))
			{
				$v = isset($v[Self::PROPERTYNAME_VALUE]) ? $v[Self::PROPERTYNAME_VALUE] : null;
			}

			/* ��ʼƴsql�������Ҫ���ֶ��������ֶ�ֵ */
			// ԭʼ���ֶ���
			$ks .= sprintf('%s,', $this->GetIdentifiers($k));
			// ԭ����ѯ��������ֶ������ϲ�����ʱʹ�ã�
			$kss .= sprintf('s.%s,', $this->GetIdentifiers($k));
			// Ŀ��������ֶ������ϲ�����ʱʹ�ã�
			$kst .= sprintf('t.%s,', $this->GetIdentifiers($k));
			// ��ֵ��ϵ���ϲ�����ʱʹ��
			$ksv .= sprintf('s.%s = t.%s,', $this->GetIdentifiers($k), $this->GetIdentifiers($k));

			// 2016-12-17��չ���ֶ�ֵ����ָ��raw���ԣ����rawΪtrue���Բ�����ʽ���ݡ�
			// �������ֵ
			if ($raw)
			{
				switch ($type)
				{
					case Self::TYPENAME_DATE:
					{
						if (is_numeric($v))
						{
							// �������ݵ�mask
							$ps .= $this->Timestamp2DatetimeFormat($v) . ',';
							// ��ѯ���ʱʹ�õ��ֶ��������ϲ�����ʱʹ�ã�
							$ss .= sprintf('%s %s,', $this->Timestamp2DatetimeFormat($v), $this->GetIdentifiers($k));
						}
						else
						{
							// �������ݵ�mask
							$ps .= $this->String2DatetimeFormat($v) . ',';
							// ��ѯ���ʱʹ�õ��ֶ��������ϲ�����ʱʹ�ã�
							$ss .= sprintf('%s %s,', $this->String2DatetimeFormat($v), $this->GetIdentifiers($k));
						}

						break;
					}

					case Self::TYPENAME_TIMESTAMP:
					{
						if (is_numeric($v))
						{
							// �������ݵ�mask
							$ps .= $v . ',';
							// ��ѯ���ʱʹ�õ��ֶ��������ϲ�����ʱʹ�ã�
							$ss .= sprintf('%s %s,', $v, $this->GetIdentifiers($k));
						}
						else
						{
							// �������ݵ�mask
							$ps .= $this->Datetime2TimestampFormat($v) . ',';
							// ��ѯ���ʱʹ�õ��ֶ��������ϲ�����ʱʹ�ã�
							$ss .= sprintf('%s %s,', $this->Datetime2TimestampFormat($v), $this->GetIdentifiers($k));
						}

						break;
					}

					case Self::TYPENAME_STRING:
					{
						// �������ݵ�mask
						$ps .= $this->GetIdentifiers($v, true) . ',';
						// ��ѯ���ʱʹ�õ��ֶ��������ϲ�����ʱʹ�ã�
						$ss .= sprintf('%s %s,', $this->GetIdentifiers($v, true), $this->GetIdentifiers($k));

						break;
					}

					default:
					{
						// �������ݵ�mask
						$ps .= $v . ',';
						// ��ѯ���ʱʹ�õ��ֶ��������ϲ�����ʱʹ�ã�
						$ss .= sprintf('%s %s,', $v, $this->GetIdentifiers($k));

						break;
					}
				}
			}
			else
			{
				switch ($type)
				{
					case Self::TYPENAME_DATE:
					{
						if (is_numeric($v))
						{
							// �������ݵ�mask
							$ps .= $this->Timestamp2DatetimeFormat('?') . ',';
							// ��ѯ���ʱʹ�õ��ֶ��������ϲ�����ʱʹ�ã�
							$ss .= sprintf('%s %s,', $this->Timestamp2DatetimeFormat('?'), $this->GetIdentifiers($k));
						}
						else
						{
							// �������ݵ�mask
							$ps .= $this->String2DatetimeFormat('?', false) . ',';
							// ��ѯ���ʱʹ�õ��ֶ��������ϲ�����ʱʹ�ã�
							$ss .= sprintf('%s %s,', $this->String2DatetimeFormat('?', false), $this->GetIdentifiers($k));
						}

						break;
					}

					case Self::TYPENAME_TIMESTAMP:
					{
						if (is_numeric($v))
						{
							// �������ݵ�mask
							$ps .= '?,';
							// ��ѯ���ʱʹ�õ��ֶ��������ϲ�����ʱʹ�ã�
							$ss .= sprintf('? %s,', $this->GetIdentifiers($k));
						}
						else
						{
							// �������ݵ�mask
							$ps .= $this->Datetime2TimestampFormat('?', false) . ',';
							// ��ѯ���ʱʹ�õ��ֶ��������ϲ�����ʱʹ�ã�
							$ss .= sprintf('%s %s,', $this->Datetime2TimestampFormat('?', false), $this->GetIdentifiers($k));
						}

						break;
					}

					default:
					{
						// �������ݵ�mask
						$ps .= '?,';
						// ��ѯ���ʱʹ�õ��ֶ��������ϲ�����ʱʹ�ã�
						$ss .= sprintf('? %s,', $this->GetIdentifiers($k));

						break;
					}
				}

				// ���ֶ�ֵ��������б���
				array_push($vs, $v);
			}
		}

		if (0 == count($vs))
		{
			return false;
		}

		// ԭʼ���ֶ���
		$ks = mb_substr($ks, 0, mb_strlen($ks, USEDCHARSET) - 1, USEDCHARSET);
		// ԭ����ѯ��������ֶ������ϲ�����ʱʹ�ã�
		$kss = mb_substr($kss, 0, mb_strlen($kss, USEDCHARSET) - 1, USEDCHARSET);
		// Ŀ��������ֶ������ϲ�����ʱʹ�ã�
		$kst = mb_substr($kst, 0, mb_strlen($kst, USEDCHARSET) - 1, USEDCHARSET);
		// ��ֵ��ϵ���ϲ�����ʱʹ��
		$ksv = mb_substr($ksv, 0, mb_strlen($ksv, USEDCHARSET) - 1, USEDCHARSET);
		// �������ݵ�mask
		$ps = mb_substr($ps, 0, mb_strlen($ps, USEDCHARSET) - 1, USEDCHARSET);
		// ��ѯ���ʱʹ�õ��ֶ��������ϲ�����ʱʹ�ã�
		$ss = mb_substr($ss, 0, mb_strlen($ss, USEDCHARSET) - 1, USEDCHARSET);

		$command = '';
		$repcmd = '';
		$inscmd = '';
		$rs = '';
		switch (DATABASE_TYPE)
		{
		case 'MYSQL':
			$repcmd = sprintf('replace into %s(%s) values (%s)', $this->GetIdentifiers($tablename), $ks, $ps);
			$inscmd = sprintf('insert into %s(%s) values (%s)', $this->GetIdentifiers($tablename), $ks, $ps);
		break;

		case 'ORACLE':
			if (is_array($refer) && count($refer))
			{
				foreach ($refer as $k => $v)
				{
					$rs .= sprintf(' s.%s = t.%s and', $this->GetIdentifiers($v), $this->GetIdentifiers($v));
				}

				$rs = mb_substr($rs, 0, mb_strlen($rs, USEDCHARSET) - 3, USEDCHARSET);
			}
			else
			{
				$rs = $refer;
			}

			if (mb_strlen($rs, USEDCHARSET))
			{
				$command =
					'merge into %s t' . PHP_EOL .
					'using (select %s from dual) s' . PHP_EOL .
					'on %s' . PHP_EOL .
					'when matched then' . PHP_EOL .
					'	update set %s' . PHP_EOL .
					'when not matched then' . PHP_EOL .
					'	insert' . PHP_EOL .
					'		(%s)' . PHP_EOL .
					'	values' . PHP_EOL .
					'		(%s)';

				$repcmd = sprintf($command,
					$this->GetIdentifiers($tablename),
					$ss,
					$rs,
					$ksv,
					$kst,
					$kss);
			}
			else
			{
				$repcmd = '';
			}

			$inscmd = sprintf('insert into %s(%s) values (%s)', $this->GetIdentifiers($tablename), $ks, $ps);
		break;

		case 'SQLSRV':
			if (is_array($refer) && count($refer))
			{
				foreach ($refer as $k => $v)
				{
					$rs .= sprintf(' s.%s = t.%s and', $this->GetIdentifiers($v), $this->GetIdentifiers($v));
				}

				$rs = mb_substr($rs, 0, mb_strlen($rs, USEDCHARSET) - 3, USEDCHARSET);
			}
			else
			{
				$rs = $refer;
			}

			if (mb_strlen($rs, USEDCHARSET))
			{
				$command =
					'merge into %s t' . PHP_EOL .
					'using (select %s) s' . PHP_EOL .
					'on %s' . PHP_EOL .
					'when matched then' . PHP_EOL .
					'	update set %s' . PHP_EOL .
					'when not matched then' . PHP_EOL .
					'	insert' . PHP_EOL .
					'		(%s)' . PHP_EOL .
					'	values' . PHP_EOL .
					'		(%s)';

				$repcmd = sprintf($command,
					$this->GetIdentifiers($tablename),
					$ss,
					$rs,
					$ksv,
					$kst,
					$kss);
			}
			else
			{
				$repcmd = '';
			}

			$inscmd = sprintf('insert into %s(%s) values (%s)', $this->GetIdentifiers($tablename), $ks, $ps);
		break;

		default:
			$this->ErrorCode = ERRORCODE_BADPARAMETER;
			$this->ErrorInfo = sprintf(ERRORINFO_BADPARAMETER, 'dbtype', DATABASE_TYPE);
			return false;
		break;
		}

		$command = $replace ? $repcmd : $inscmd;
		$return = $this->PDO_Execute($command, $vs);
		$this->ErrorCode = $this->Database->GetErrorCode();
		$this->ErrorInfo = $this->Database->GetErrorInfo();
		return $return;
	}

	/**
	 * 2016-12-17��չ���ֶ�ֵ����ָ��raw���ԣ����rawΪtrue���Բ�����ʽ���ݡ�
	 * @note ִ��һ���޸Ĺ���
	 * @param string $tablename ����
	 * @param string $fields �ֶΣ��ֶ���=�ֶ�ֵ��
	 * @param array $ands ������and�����ֶ���=�ֶ�ֵ��
	 * @param array $ors ������or�����ֶ���=�ֶ�ֵ��
	 * @return bool|mixed|null
	 */
	protected function PDO_Update($tablename, $fields, $ands = null, $ors = null)
	{
		if (null == $this->Database)
		{
			return false;
		}
		if (is_object($fields))
		{
			$fields = (array)$fields;
		}

		$vs = array();

		if (is_array($fields))
		{
			$fs = '';
			foreach ($fields as $k => $v)
			{
				if (null === $v)
				{
					continue;
				}

				if (is_object($v))
				{
					$v = (array)$v;
				}

				// 2016-12-17��չ���ֶ�ֵ����ָ��raw���ԣ����rawΪtrue���Բ�����ʽ���ݡ�
				$raw = isset($v[Self::PROPERTYNAME_RAW]) ? $v[Self::PROPERTYNAME_RAW] : false;
				$type = isset($v[Self::PROPERTYNAME_TYPE]) ? $v[Self::PROPERTYNAME_TYPE] : Self::TYPENAME_RAW;
				// ֵ
				if (is_array($v))
				{
					$v = isset($v[Self::PROPERTYNAME_VALUE]) ? $v[Self::PROPERTYNAME_VALUE] : null;
				}

				if ($raw)
				{
					switch ($type)
					{
						case Self::TYPENAME_DATE:
						{
							if (is_numeric($v))
							{
								$fs .= sprintf('%s = %s,', $this->GetIdentifiers($k, false, '.'), $this->Timestamp2DatetimeFormat($v));
							}
							else
							{
								$fs .= sprintf('%s = %s,', $this->GetIdentifiers($k, false, '.'), $this->String2DatetimeFormat($v));
							}
							break;
						}

						case Self::TYPENAME_TIMESTAMP:
						{
							if (is_numeric($v))
							{
								$fs .= sprintf('%s = %s,', $this->GetIdentifiers($k, false, '.'), $v);
							}
							else
							{
								$fs .= sprintf('%s = %s,', $this->GetIdentifiers($k, false, '.'), $this->Datetime2TimestampFormat($v));
							}

							break;
						}

						case Self::TYPENAME_STRING:
						{
							$fs .= sprintf('%s = %s,', $this->GetIdentifiers($k, false, '.'), $this->GetIdentifiers($v, true));
							break;
						}

						default:
						{
							$fs .= sprintf('%s = %s,', $this->GetIdentifiers($k, false, '.'), $v);
							break;
						}
					}
				}
				else
				{
					switch ($type)
					{
						case Self::TYPENAME_DATE:
						{
							if (is_numeric($v))
							{
								$fs .= sprintf('%s = %s,', $this->GetIdentifiers($k, false, '.'), $this->Timestamp2DatetimeFormat('?'));
							}
							else
							{
								$fs .= sprintf('%s = %s,', $this->GetIdentifiers($k, false, '.'), $this->String2DatetimeFormat('?', false));
							}
							break;
						}

						case Self::TYPENAME_TIMESTAMP:
						{
							if (is_numeric($v))
							{
								$fs .= sprintf('%s = ?,', $this->GetIdentifiers($k, false, '.'));
							}
							else
							{
								$fs .= sprintf('%s = %s,', $this->GetIdentifiers($k, false, '.'), $this->Datetime2TimestampFormat('?', false));
							}

							break;
						}

						default:
						{
							$fs .= sprintf('%s = ?,', $this->GetIdentifiers($k, false, '.'));
							break;
						}
					}

					array_push($vs, $v);
				}
			}

			if (empty($fs))
			{
				return false;
			}
			$fs = mb_substr($fs, 0, mb_strlen($fs, USEDCHARSET) - 1, USEDCHARSET);
		}
		else
		{
			$fs = $fields;
		}

		$ws = $this->GetWheres($ands, $ors);
		if (empty($ws[Self::CONDITION_NAMES]))
		{
			$command = sprintf('update %s set %s', $this->GetIdentifiers($tablename, false, ','), $fs);
			$return = $this->PDO_Execute($command, $vs);
		}
		else
		{
			$command = sprintf('update %s set %s where %s', $this->GetIdentifiers($tablename, false, ','), $fs, $ws[Self::CONDITION_NAMES]);
			$return = $this->PDO_Execute($command, $vs, $ws[Self::CONDITION_VALUE]);
		}

		$this->ErrorCode = $this->Database->GetErrorCode();
		$this->ErrorInfo = $this->Database->GetErrorInfo();
		return $return;
	}

	/**
	 * @note ִ��һ��ɾ������
	 * @param string $tablename ����
	 * @param array $ands ������and�����ֶ���=�ֶ�ֵ��
	 * @param array $ors ������or�����ֶ���=�ֶ�ֵ��
	 * @return bool|mixed|null
	 */
	protected function PDO_Delete($tablename, $ands = null, $ors = null)
	{
		if (null == $this->Database)
		{
			return false;
		}

		$ws = $this->GetWheres($ands, $ors);
		if (empty($ws[Self::CONDITION_NAMES]))
		{
			$command = sprintf('delete from %s', $this->GetIdentifiers($tablename));
			$return = $this->PDO_Execute($command);
		}
		else
		{
			$command = sprintf('delete from %s where %s', $this->GetIdentifiers($tablename), $ws[Self::CONDITION_NAMES]);
			$return = $this->PDO_Execute($command, $ws[Self::CONDITION_VALUE]);
		}

		$this->ErrorCode = $this->Database->GetErrorCode();
		$this->ErrorInfo = $this->Database->GetErrorInfo();
		return $return;
	}


	/**
	 * 2017-03-31 ���ӷ���֧��
	 * @note ִ��һ����ѯ����
	 * @param string|array $tables ������2017-03-03��������֧�֣�
	 * @param string|array $fields Ҫ��ѯ���ֶΣ�2016-12-08�����������֧�֣���ʽΪ������=>ԭ�ֶ�/���ʽ��
	 * @param array $ands ������and�����ֶ���=�ֶ�ֵ��
	 * @param array $ors ������or�����ֶ���=�ֶ�ֵ��
	 * @param array $orders �����ֶΣ��ֶ���=����˳��
	 * @param array $groups �����ֶΣ��ֶ�����������
	 * @return bool|mixed|null
	 */
	protected function PDO_Select($tables, $fields, $ands = null, $ors = null, $orders = null, $groups = null)
	{
		if (null == $this->Database)
		{
			return false;
		}

		$tables = $this->GetSelectTables($tables);
		$fields = $this->GetSelectFields($fields)[Self::FIELDNAME_FIELD];
		if (empty($tables) || empty($fields))
		{
			return false;
		}

		$gs = $this->GetGroups($groups);
		if (!empty($gs))
		{
			$gs = ' group by ' . $gs;
		}

		$os = $this->GetOrders($orders);
		if (!empty($os))
		{
			$os = ' order by ' . $os;
		}

		$ws = $this->GetWheres($ands, $ors);
		if (empty($ws[Self::CONDITION_NAMES]))
		{
			$command = sprintf('select %s from %s%s%s', $fields, $tables, $gs, $os);
			$return = $this->PDO_Request($command);
		}
		else
		{
			$command = sprintf('select %s from %s where %s%s%s', $fields, $tables, $ws[Self::CONDITION_NAMES], $gs, $os);
			$return = $this->PDO_Request($command, $ws[Self::CONDITION_VALUE]);
		}

		//var_dump($command);
		$this->ErrorCode = $this->Database->GetErrorCode();
		$this->ErrorInfo = $this->Database->GetErrorInfo();
		return $return;
	}


	/**
	 * 2016-08-16���ӡ�2017-03-31���ӷ���֧��
	 * @note ִ��һ����ѯ���̣���ҳ��
	 * @param string|array $tables ������2017-03-03��������֧�֣�
	 * @param string|array $fields Ҫ��ѯ���ֶΣ�2016-12-08�����������֧�֣���ʽΪ������=>ԭ�ֶ�/���ʽ��
	 * @param array $ands ������and�����ֶ���=�ֶ�ֵ��
	 * @param array $ors ������or�����ֶ���=�ֶ�ֵ��
	 * @param array $orders �����ֶΣ��ֶ���=����˳��
	 * @param array $groups �����ֶΣ��ֶ�����������
	 * @param int $pageindex ҳ��ţ�1Ϊ��һ����ţ�
	 * @param int $pagesize һҳ��С
	 * @return bool|mixed|null
	 * @note Ӧ��
	 */
	protected function PDO_Select_Page($tables, $fields, $ands = null, $ors = null, $orders = null, $groups = null, $pageindex = 1, $pagesize = 20)
	{
		if (null == $this->Database)
		{
			return false;
		}

		// �ɴ������
		if (is_numeric($groups))
		{
			$pagesize = $pageindex;
			$pageindex = $groups;
			$groups = null;
		}

		// ��ʼ���
		$start = ($pageindex - 1) * $pagesize + 1;
		// ��ֹ���
		$stop = $pageindex * $pagesize;

		// ��ҳ�õ��ֶ���
		$newfieldname = $this->GetIdentifiers($this->GetRandString('nf_'));
		// ��ҳ�õı���
		$newtablename = $this->GetIdentifiers($this->GetRandString('nt_'));

		// Ҫ��ѯ�ı�
		$tables = $this->GetSelectTables($tables);
		// Ҫ��ѯ���ֶ�
		$fields = $this->GetSelectFields($fields);

		if (empty($tables) || empty($fields[Self::FIELDNAME_FIELD]) || empty($fields[Self::FIELDNAME_ALIAS]))
		{
			return false;
		}

		$gs = $this->GetGroups($groups);
		if (!empty($gs))
		{
			$gs = ' group by ' . $gs;
		}

		$os = $this->GetOrders($orders);
		if (!empty($os))
		{
			$os = ' order by ' . $os;
		}

		$ws = $this->GetWheres($ands, $ors);
		switch (DATABASE_TYPE)
		{
		case 'MYSQL':
			if (empty($ws[Self::CONDITION_NAMES]))
			{
				$command =
					'select' . PHP_EOL .
					'	%s' . PHP_EOL .
					'from' . PHP_EOL .
					'	(' . PHP_EOL .
					'		select' . PHP_EOL .
					'			%s,' . PHP_EOL .
					'			@i := @i + 1 %s' . PHP_EOL .
					'		from' . PHP_EOL .
					'			%s,' . PHP_EOL .
					'			(select @i := 0) %s' . PHP_EOL .
					'		%s' . PHP_EOL .
					'		$s' . PHP_EOL .
					'		limit %d' . PHP_EOL .
					'	) %s' . PHP_EOL .
					'where' . PHP_EOL .
					'	%s >= %d';
				$command = sprintf($command,
					$fields[Self::FIELDNAME_ALIAS],
					$fields[Self::FIELDNAME_FIELD],
					$newfieldname,
					$tables,
					$newtablename,
					$gs,
					$os,
					$stop,
					$newtablename,
					$newfieldname,
					$start
				);
				//var_dump($command);
				$return = $this->PDO_Request($command);
			}
			else
			{
				$command =
					'select' . PHP_EOL .
					'	%s' . PHP_EOL .
					'from' . PHP_EOL .
					'	(' . PHP_EOL .
					'		select' . PHP_EOL .
					'			%s,' . PHP_EOL .
					'			@i := @i + 1 %s' . PHP_EOL .
					'		from' . PHP_EOL .
					'			%s,' . PHP_EOL .
					'			(select @i := 0) %s' . PHP_EOL .
					'		where' . PHP_EOL .
					'			%s' . PHP_EOL .
					'		%s' . PHP_EOL .
					'		%s' . PHP_EOL .
					'		limit %d' . PHP_EOL .
					'	) %s' . PHP_EOL .
					'where' . PHP_EOL .
					'	%s >= %d';
				$command = sprintf($command,
					$fields[Self::FIELDNAME_ALIAS],
					$fields[Self::FIELDNAME_FIELD],
					$newfieldname,
					$tables,
					$newtablename,
					$ws[Self::CONDITION_NAMES],
					$gs,
					$os,
					$stop,
					$newtablename,
					$newfieldname,
					$start
				);
				//var_dump($command);
				$return = $this->PDO_Request($command, $ws[Self::CONDITION_VALUE]);
			}
		break;

		case 'ORACLE':
			if (empty($ws[Self::CONDITION_NAMES]))
			{
				$command =
					'select' . PHP_EOL .
					'	%s' . PHP_EOL .
					'from' . PHP_EOL .
					'	(' . PHP_EOL .
					'		select' . PHP_EOL .
					'			%s,' . PHP_EOL .
					'			row_number() over(%s) %s' . PHP_EOL .
					'		from' . PHP_EOL .
					'			%s' . PHP_EOL .
					//'		where' . PHP_EOL .
					//'			rownum <= %d' . PHP_EOL .
					'		%s' . PHP_EOL .
					'	) %s' . PHP_EOL .
					'where' . PHP_EOL .
					'	%s between %d and %d';
				$command = sprintf($command,
					$fields[Self::FIELDNAME_ALIAS],
					$fields[Self::FIELDNAME_FIELD],
					$os,
					$newfieldname,
					$tables,
					//$stop,
					$gs,
					$newtablename,
					$newfieldname,
					$start,
					$stop
				);
				//var_dump($command);
				$return = $this->PDO_Request($command);
			}
			else
			{
				$command =
					'select' . PHP_EOL .
					'	%s' . PHP_EOL .
					'from' . PHP_EOL .
					'	(' . PHP_EOL .
					'		select' . PHP_EOL .
					'			%s,' . PHP_EOL .
					'			row_number() over(%s) %s' . PHP_EOL .
					'		from' . PHP_EOL .
					'			%s' . PHP_EOL .
					'		where' . PHP_EOL .
					//'			rownum <= %d and' . PHP_EOL .
					'			%s' . PHP_EOL .
					'		%s' . PHP_EOL .
					'	) %s' . PHP_EOL .
					'where' . PHP_EOL .
					'	%s between %d and %d';
				$command = sprintf($command,
					$fields[Self::FIELDNAME_ALIAS],
					$fields[Self::FIELDNAME_FIELD],
					$os,
					$newfieldname,
					$tables,
					//$stop,
					$ws[Self::CONDITION_NAMES],
					$gs,
					$newtablename,
					$newfieldname,
					$start,
					$stop
				);
				//var_dump($command);
				$return = $this->PDO_Request($command, $ws[Self::CONDITION_VALUE]);
			}
		break;

		case 'SQLSRV':
			if (empty($ws[Self::CONDITION_NAMES]))
			{
				$command =
					'select' . PHP_EOL .
					'	%s' . PHP_EOL .
					'from' . PHP_EOL .
					'	(' . PHP_EOL .
					'		select' . PHP_EOL .
					//'			top %d' . PHP_EOL .
					'			%s,' . PHP_EOL .
					'			row_number() over(%s) %s' . PHP_EOL .
					'		from' . PHP_EOL .
					'			%s' . PHP_EOL .
					'		%s' . PHP_EOL .
					'	) %s' . PHP_EOL .
					'where' . PHP_EOL .
					'	%s between %d and %d';
				$command = sprintf($command,
					$fields[Self::FIELDNAME_ALIAS],
					//$stop,
					$fields[Self::FIELDNAME_FIELD],
					$os,
					$newfieldname,
					$tables,
					$gs,
					$newtablename,
					$newfieldname,
					$start,
					$stop
				);
				//var_dump($command);
				$return = $this->PDO_Request($command);
			}
			else
			{
				$command =
					'select' . PHP_EOL .
					'	%s' . PHP_EOL .
					'from' . PHP_EOL .
					'	(' . PHP_EOL .
					'		select' . PHP_EOL .
					//'			top %d' . PHP_EOL .
					'			%s,' . PHP_EOL .
					'			row_number() over(%s) %s' . PHP_EOL .
					'		from' . PHP_EOL .
					'			%s' . PHP_EOL .
					'		where' . PHP_EOL .
					'			%s' . PHP_EOL .
					'		%s' . PHP_EOL .
					'	) %s' . PHP_EOL .
					'where' . PHP_EOL .
					'	%s between %d and %d';
				$command = sprintf($command,
					$fields[Self::FIELDNAME_ALIAS],
					//$stop,
					$fields[Self::FIELDNAME_FIELD],
					$os,
					$newfieldname,
					$tables,
					$ws[Self::CONDITION_NAMES],
					$gs,
					$newtablename,
					$newfieldname,
					$start,
					$stop
				);
				//var_dump($command);
				$return = $this->PDO_Request($command, $ws[Self::CONDITION_VALUE]);
			}
		break;

		default:
			$this->ErrorCode = ERRORCODE_BADPARAMETER;
			$this->ErrorInfo = sprintf(ERRORINFO_BADPARAMETER, 'dbtype', DATABASE_TYPE);
			return false;
		break;
		}

		$this->ErrorCode = $this->Database->GetErrorCode();
		$this->ErrorInfo = $this->Database->GetErrorInfo();
		return $return;
	}

	/**
	 * 2017-02-17���ӡ�2017-03-31���ӷ���֧��
	 * @note ��������IJ������ɶ�Ӧ��sql��䡣
	 * @param string $request �Ӳ�ѯ��
	 * @param string|array $tablename ����������֧�ֱ�����
	 * @param bool $ispage �Ƿ���Ҫ��ҳ��
	 * @param string $fields Ҫ��ѯ���ֶΣ�����=>ԭ�ֶ�/���ʽ��
	 * @param array $ands ������and�����ֶ���=�ֶ�ֵ��
	 * @param array $ors ������or�����ֶ���=�ֶ�ֵ��
	 * @param array $orders �����ֶΣ��ֶ���=����˳��
	 * @param array $groups �����ֶΣ��ֶ�����������
	 * @param int $pageindex ҳ��ţ�1Ϊ��һ����ţ�
	 * @param int $pagesize һҳ��С
	 * @return bool|mixed|null
	 * @note Ӧ��
	 */
	private function GetSelectPageCommand($request, $tablename, $ispage, $fields, $ands = null, $ors = null, $orders = null, $groups = null, $pageindex = 1, $pagesize = 20)
	{
		$return = array(
			Self::COMMAND_LINE => '',
			Self::COMMAND_VARS => array(),
		);

		// ��ҳ�õ��ֶ���
		$newfieldname = $this->GetIdentifiers($this->GetRandString('nf_'));
		// ��ҳ�õı���
		$newtablename = $this->GetIdentifiers($this->GetRandString('nt_'));
		// �Ӳ�ѯ����
		$newrequest = $this->GetIdentifiers($this->GetRandString('nr_'));

		// ����
		$tablename = $this->GetSelectTables($tablename);
		// �ֶ���
		$fields = $this->GetSelectFields($fields);
		if (empty($tablename) || empty($fields[Self::FIELDNAME_FIELD]) || empty($fields[Self::FIELDNAME_ALIAS]))
		{
			return $return;
		}

		$gs = $this->GetGroups($groups);
		if (!empty($gs))
		{
			$gs = ' group by ' . $gs;
		}

		$os = $this->GetOrders($orders);
		if (!empty($os))
		{
			$os = ' order by ' . $os;
		}

		if ($ispage)
		{
			// ��ʼ���
			$start = ($pageindex - 1) * $pagesize + 1;
			// ��ֹ���
			$stop = $pageindex * $pagesize;

			$ws = $this->GetWheres($ands, $ors);
			switch (DATABASE_TYPE)
			{
			case 'MYSQL':
				if (empty($ws[Self::CONDITION_NAMES]))
				{
					$command =
						'select' . PHP_EOL .
						'	%s' . PHP_EOL .
						'from' . PHP_EOL .
						'	(' . PHP_EOL .
						'		select' . PHP_EOL .
						'			%s,' . PHP_EOL .
						'			@i := @i + 1 %s' . PHP_EOL .
						'		from' . PHP_EOL .
						'%s' .
						'			%s,' . PHP_EOL .
						'			(select @i := 0) %s' . PHP_EOL .
						'		%s' . PHP_EOL .
						'		%s' . PHP_EOL .
						'		limit %d' . PHP_EOL .
						'	) %s' . PHP_EOL .
						'where' . PHP_EOL .
						'	%s >= %d';
					$command = sprintf($command,
						$fields[Self::FIELDNAME_ALIAS],
						$fields[Self::FIELDNAME_FIELD],
						$newfieldname,
						empty($request) ? '' : '			(' . $request . ') ' . $newrequest . ',' . PHP_EOL,
						$tablename,
						$newtablename,
						$gs,
						$os,
						$stop,
						$newtablename,
						$newfieldname,
						$start
					);

					$return[Self::COMMAND_LINE] = $command;
					$return[Self::COMMAND_VARS] = array();
				}
				else
				{
					$command =
						'select' . PHP_EOL .
						'	%s' . PHP_EOL .
						'from' . PHP_EOL .
						'	(' . PHP_EOL .
						'		select' . PHP_EOL .
						'			%s,' . PHP_EOL .
						'			@i := @i + 1 %s' . PHP_EOL .
						'		from' . PHP_EOL .
						'%s' .
						'			%s,' . PHP_EOL .
						'			(select @i := 0) %s' . PHP_EOL .
						'		where' . PHP_EOL .
						'			%s' . PHP_EOL .
						'			%s' . PHP_EOL .
						'		%s' . PHP_EOL .
						'		limit %d' . PHP_EOL .
						'	) %s' . PHP_EOL .
						'where' . PHP_EOL .
						'	%s >= %d';
					$command = sprintf($command,
						$fields[Self::FIELDNAME_ALIAS],
						$fields[Self::FIELDNAME_FIELD],
						$newfieldname,
						empty($request) ? '' : '			(' . $request . ') ' . $newrequest . ',' . PHP_EOL,
						$tablename,
						$newtablename,
						$ws[Self::CONDITION_NAMES],
						$gs,
						$os,
						$stop,
						$newtablename,
						$newfieldname,
						$start
					);

					$return[Self::COMMAND_LINE] = $command;
					$return[Self::COMMAND_VARS] = $ws[Self::CONDITION_VALUE];
				}
			break;

			case 'ORACLE':
				if (empty($ws[Self::CONDITION_NAMES]))
				{
					$command =
						'select' . PHP_EOL .
						'	%s' . PHP_EOL .
						'from' . PHP_EOL .
						'	(' . PHP_EOL .
						'		select' . PHP_EOL .
						'			%s,' . PHP_EOL .
						'			row_number() over(%s) %s' . PHP_EOL .
						'		from' . PHP_EOL .
						'%s' .
						'			%s' . PHP_EOL .
						//'		where' . PHP_EOL .
						//'			rownum <= %d' . PHP_EOL .
						'		%s' . PHP_EOL .
						'	) %s' . PHP_EOL .
						'where' . PHP_EOL .
						'	%s between %d and %d';
					$command = sprintf($command,
						$fields[Self::FIELDNAME_ALIAS],
						$fields[Self::FIELDNAME_FIELD],
						$os,
						$newfieldname,
						empty($request) ? '' : '			(' . $request . ') ' . $newrequest . ',' . PHP_EOL,
						$tablename,
						//$stop,
						$gs,
						$newtablename,
						$newfieldname,
						$start,
						$stop
					);

					$return[Self::COMMAND_LINE] = $command;
					$return[Self::COMMAND_VARS] = array();
				}
				else
				{
					$command =
						'select' . PHP_EOL .
						'	%s' . PHP_EOL .
						'from' . PHP_EOL .
						'	(' . PHP_EOL .
						'		select' . PHP_EOL .
						'			%s,' . PHP_EOL .
						'			row_number() over(%s) %s' . PHP_EOL .
						'		from' . PHP_EOL .
						'%s' .
						'			%s' . PHP_EOL .
						'		where' . PHP_EOL .
						//'			rownum <= %d and' . PHP_EOL .
						'			%s' . PHP_EOL .
						'		%s' . PHP_EOL .
						'	) %s' . PHP_EOL .
						'where' . PHP_EOL .
						'	%s between %d and %d';
					$command = sprintf($command,
						$fields[Self::FIELDNAME_ALIAS],
						$fields[Self::FIELDNAME_FIELD],
						$os,
						$newfieldname,
						empty($request) ? '' : '			(' . $request . ') ' . $newrequest . ',' . PHP_EOL,
						$tablename,
						//$stop,
						$ws[Self::CONDITION_NAMES],
						$gs,
						$newtablename,
						$newfieldname,
						$start,
						$stop
					);

					$return[Self::COMMAND_LINE] = $command;
					$return[Self::COMMAND_VARS] = $ws[Self::CONDITION_VALUE];
				}
			break;

			case 'SQLSRV':
				if (empty($ws[Self::CONDITION_NAMES]))
				{
					$command =
						'select' . PHP_EOL .
						'	%s' . PHP_EOL .
						'from' . PHP_EOL .
						'	(' . PHP_EOL .
						'		select' . PHP_EOL .
						//'			top %d' . PHP_EOL .
						'			%s,' . PHP_EOL .
						'			row_number() over(%s) %s' . PHP_EOL .
						'		from' . PHP_EOL .
						'%s' .
						'			%s' . PHP_EOL .
						'		%s' . PHP_EOL .
						'	) %s' . PHP_EOL .
						'where' . PHP_EOL .
						'	%s between %d and %d';
					$command = sprintf($command,
						$fields[Self::FIELDNAME_ALIAS],
						//$stop,
						$fields[Self::FIELDNAME_FIELD],
						$os,
						$newfieldname,
						empty($request) ? '' : '			(' . $request . ') ' . $newrequest . ',' . PHP_EOL,
						$tablename,
						$gs,
						$newtablename,
						$newfieldname,
						$start,
						$stop
					);

					$return[Self::COMMAND_LINE] = $command;
					$return[Self::COMMAND_VARS] = array();
				}
				else
				{
					$command =
						'select' . PHP_EOL .
						'	%s' . PHP_EOL .
						'from' . PHP_EOL .
						'	(' . PHP_EOL .
						'		select' . PHP_EOL .
						//'			top %d' . PHP_EOL .
						'			%s,' . PHP_EOL .
						'			row_number() over(%s) %s' . PHP_EOL .
						'		from' . PHP_EOL .
						'%s' .
						'			%s' . PHP_EOL .
						'		where' . PHP_EOL .
						'			%s' . PHP_EOL .
						'		%s' . PHP_EOL .
						'	) %s' . PHP_EOL .
						'where' . PHP_EOL .
						'	%s between %d and %d';
					$command = sprintf($command,
						$fields[Self::FIELDNAME_ALIAS],
						//$stop,
						$fields[Self::FIELDNAME_FIELD],
						$os,
						$newfieldname,
						empty($request) ? '' : '			(' . $request . ') ' . $newrequest . ',' . PHP_EOL,
						$tablename,
						$ws[Self::CONDITION_NAMES],
						$gs,
						$newtablename,
						$newfieldname,
						$start,
						$stop
					);

					$return[Self::COMMAND_LINE] = $command;
					$return[Self::COMMAND_VARS] = $ws[Self::CONDITION_VALUE];
				}
			break;

			}

			return $return;
		}
		else
		{
			$ws = $this->GetWheres($ands, $ors);
			switch (DATABASE_TYPE)
			{
			case 'MYSQL':
				if (empty($ws[Self::CONDITION_NAMES]))
				{
					$command =
						'select' . PHP_EOL .
						'	%s' . PHP_EOL .
						'from' . PHP_EOL .
						'%s' .
						'	%s' . PHP_EOL .
						'	%s' . PHP_EOL .
						'	%s';
					$command = sprintf($command,
						$fields[Self::FIELDNAME_FIELD],
						empty($request) ? '' : '	(' . $request . ') ' . $newrequest . ',' . PHP_EOL,
						$tablename,
						$gs,
						$os
					);

					$return[Self::COMMAND_LINE] = $command;
					$return[Self::COMMAND_VARS] = array();
				}
				else
				{
					$command =
						'select' . PHP_EOL .
						'	%s' . PHP_EOL .
						'from' . PHP_EOL .
						'%s' .
						'	%s' . PHP_EOL .
						'where' . PHP_EOL .
						'	%s' . PHP_EOL .
						'	%s' . PHP_EOL .
						'	%s';
					$command = sprintf($command,
						$fields[Self::FIELDNAME_FIELD],
						empty($request) ? '' : '	(' . $request . ') ' . $newrequest . ',' . PHP_EOL,
						$tablename,
						$ws[Self::CONDITION_NAMES],
						$gs,
						$os
					);

					$return[Self::COMMAND_LINE] = $command;
					$return[Self::COMMAND_VARS] = $ws[Self::CONDITION_VALUE];
				}
			break;

			case 'ORACLE':
				if (empty($ws[Self::CONDITION_NAMES]))
				{
					$command =
						'select' . PHP_EOL .
						'	%s' . PHP_EOL .
						'from' . PHP_EOL .
						'%s' .
						'	%s' . PHP_EOL .
						'	%s' . PHP_EOL .
						'	%s';
					$command = sprintf($command,
						$fields[Self::FIELDNAME_FIELD],
						empty($request) ? '' : '	(' . $request . ') ' . $newrequest . ',' . PHP_EOL,
						$tablename,
						$gs,
						$os
					);

					$return[Self::COMMAND_LINE] = $command;
					$return[Self::COMMAND_VARS] = array();
				}
				else
				{
					$command =
						'select' . PHP_EOL .
						'	%s' . PHP_EOL .
						'from' . PHP_EOL .
						'%s' .
						'	%s' . PHP_EOL .
						'where' . PHP_EOL .
						'	%s' . PHP_EOL .
						'	%s' . PHP_EOL .
						'	%s';
					$command = sprintf($command,
						$fields[Self::FIELDNAME_FIELD],
						empty($request) ? '' : '	(' . $request . ') ' . $newrequest . ',' . PHP_EOL,
						$tablename,
						$ws[Self::CONDITION_NAMES],
						$gs,
						$os
					);

					$return[Self::COMMAND_LINE] = $command;
					$return[Self::COMMAND_VARS] = $ws[Self::CONDITION_VALUE];
				}
			break;

			case 'SQLSRV':
				if (empty($ws[Self::CONDITION_NAMES]))
				{
					$command =
						'select' . PHP_EOL .
						'	%s' . PHP_EOL .
						'from' . PHP_EOL .
						'%s' .
						'	%s' . PHP_EOL .
						'	%s' . PHP_EOL .
						'	%s';
					$command = sprintf($command,
						$fields[Self::FIELDNAME_FIELD],
						empty($request) ? '' : '	(' . $request . ') ' . $newrequest . ',' . PHP_EOL,
						$tablename,
						$gs,
						$os
					);

					$return[Self::COMMAND_LINE] = $command;
					$return[Self::COMMAND_VARS] = array();
				}
				else
				{
					$command =
						'select' . PHP_EOL .
						'	%s' . PHP_EOL .
						'from' . PHP_EOL .
						'%s' .
						'	%s' . PHP_EOL .
						'where' . PHP_EOL .
						'	%s' . PHP_EOL .
						'	%s' . PHP_EOL .
						'	%s';
					$command = sprintf($command,
						$fields[Self::FIELDNAME_FIELD],
						empty($request) ? '' : '	(' . $request . ') ' . $newrequest . ',' . PHP_EOL,
						$tablename,
						$ws[Self::CONDITION_NAMES],
						$gs,
						$os
					);

					$return[Self::COMMAND_LINE] = $command;
					$return[Self::COMMAND_VARS] = $ws[Self::CONDITION_VALUE];
				}
			break;

			}

			return $return;
		}
	}


	/**
	 * 2017-02-17����
	 * @note ִ��һ����ѯ���̣���ҳ��
	 *       ���ע�������ʱ��ʹ�������ӷ�ʽ��ѯ���ݡ�oracle��sqlserver���Ҫʹ���������ӣ���Ҫ�ֶ���ǹ����ֶε����ӷ�ʽ��
	 *       ����
	 *          oracle�У�    ��1.�ֶ�1 = ��2.�ֶ�2(+) �ȼ� ��1 left join ��2 on ��1.�ֶ�1 = ��2.�ֶ�2
	 *          sqlserver�У� ��1.�ֶ�1 *= ��2.�ֶ�2   �ȼ� ��1 left join ��2 on ��1.�ֶ�1 = ��2.�ֶ�2
	 * @param array $tables �������б�
	 * @param string $pagetable Ҫ��ҳ�ı�����Ϊ�����ʾ���б�ͬ����ҳ��
	 * @param string $fields Ҫ��ѯ���ֶΣ�����=>ԭ�ֶ�/���ʽ��
	 * @param array $ands ������and�����ֶ���=�ֶ�ֵ��
	 * @param array $ors ������or�����ֶ���=�ֶ�ֵ��
	 * @param array $orders �����ֶΣ��ֶ���=����˳��
	 * @param array $groups �����ֶΣ��ֶ�����������
	 * @param int $pageindex ҳ��ţ�1Ϊ��һ����ţ�
	 * @param int $pagesize һҳ��С
	 * @return bool|mixed|null
	 * @note Ӧ��
	 */
	protected function PDO_Select_Page_2($tables, $pagetable, $fields, $ands = null, $ors = null, $orders = null, $groups = null, $pageindex = 1, $pagesize = 20)
	{
		if (null == $this->Database)
		{
			return false;
		}

		// �ɴ������
		if (is_numeric($groups))
		{
			$pagesize = $pageindex;
			$pageindex = $groups;
			$groups = null;
		}

		$fields = array_values((array)$fields);
		$ands = array_values((array)$ands);
		$ors = array_values((array)$ors);

		$commandline = '';
		$commandvars = array();
		$commandfield = array();
		$index = 0;

		foreach ($tables as $tablealias => $tablename)
		{
			$t = $commandfield;
			$commandfield = array();
			foreach ($t as $k => $v)
			{
				array_push($commandfield, (is_numeric($k) || empty($k) ? $v : $k));
			}

			$fields[$index] = isset($fields[$index]) ? (array)$fields[$index] : array();
			if (!empty($fields[$index]))
			{
				foreach ($fields[$index] as $k => $v)
				{
					if (is_numeric($k) || empty($k))
						array_push($commandfield, $v);
					else
						$commandfield[$k] = $v;
				}
			}

			$command = $this->GetSelectPageCommand($commandline,
				array($tablealias => $tablename),
				strcasecmp($tablename, $pagetable) == 0,
				$commandfield,
				isset($ands[$index]) ? $ands[$index] : null,
				isset($ors[$index]) ? $ors[$index] : null,
				empty($orders) ? null : $orders[$index],
				empty($groups) ? null : $groups[$index],
				$pageindex,
				$pagesize
			);

			$commandline = $command[Self::COMMAND_LINE];
			$commandvars += $command[Self::COMMAND_VARS];

			$index++;
		}
		//OutputDebugMessage($commandline);
		//var_dump($commandline);
		//var_dump($commandvars);
		$return = $this->PDO_Request($commandline, $commandvars);
		$this->ErrorCode = $this->Database->GetErrorCode();
		$this->ErrorInfo = $this->Database->GetErrorInfo();
		return $return;
	}


	/**
	 * 2016-12-08����
	 * @note �ַ���ת��Ϊ�����͵ı��ʽ
	 * @param string $st Ҫת�����ֶλ���ʽ
	 * @param bool $quoted �Ƿ���Ҫ�������ӣ�����
	 * @return string
	 * @note Ӧ��
	 */
	protected function String2DatetimeFormat($st, $quoted = true)
	{
		if ($quoted)
		{
			$st = $this->GetIdentifiers($st, true);
		}

		switch (DATABASE_TYPE)
		{
		case 'MYSQL':
			return "(STR_TO_DATE({$st}, '%Y-%m-%d %H:%i:%s'))";
		break;

		case 'ORACLE':
			return "(to_date({$st}, 'yyyy-mm-dd hh24:mi:ss'))";
		break;

		case 'SQLSRV':
			return "(convert(datetime, {$st}, 120))";
		break;

		default:
			return "";
		break;
		}
	}


	/**
	 * 2016-12-08����
	 * @note ����ת��Ϊ�ַ����͵ı��ʽ
	 * @param string $dt Ҫת�����ֶλ���ʽ
	 * @param bool $quoted �Ƿ���Ҫ�������ӣ�����
	 * @return string
	 * @note Ӧ��
	 */
	protected function Datetime2StringFormat($dt, $quoted = true)
	{
		if ($quoted)
		{
			$dt = $this->GetIdentifiers($dt, true);
		}

		switch (DATABASE_TYPE)
		{
		case 'MYSQL':
			return "(DATE_FORMAT({$dt}, '%Y-%m-%d %H:%i:%s'))";
		break;

		case 'ORACLE':
			return "(to_char({$dt}, 'yyyy-mm-dd hh24:mi:ss'))";
		break;

		case 'SQLSRV':
			return "(convert(varchar, {$dt}, 120))";
		break;

		default:
			return "";
		break;
		}
	}


	/**
	 * 2016-12-08����
	 * @note ʱ���ת��Ϊ�����͵ı��ʽ
	 * @param string $ts Ҫת�����ֶλ���ʽ
	 * @return string
	 * @note Ӧ��
	 */
	protected function Timestamp2DatetimeFormat($ts)
	{
		switch (DATABASE_TYPE)
		{
		case 'MYSQL':
			return "(FROM_UNIXTIME({$ts}))";
		break;

		case 'ORACLE':
			return "(to_date('19700101', 'yyyymmdd') + {$ts} / 86400 + to_number(substr(tz_offset(sessiontimezone), 1, 3)) / 24)";
		break;

		case 'SQLSRV':
			return "(dateadd(S, {$ts} + 8 * 3600, '1970-01-01 00:00:00'))";
		break;

		default:
			return "";
		break;
		}
	}



	/**
	 * 2016-12-08����
	 * @note ����ת��Ϊʱ����͵ı��ʽ
	 * @param string $ds Ҫת�����ֶλ���ʽ
	 * @param bool $quoted �Ƿ���Ҫ�������ӣ�����
	 * @return string
	 * @note Ӧ��
	 */
	protected function Datetime2TimestampFormat($ds, $quoted = true)
	{
		if ($quoted)
		{
			$ds = $this->GetIdentifiers($ds, true);
		}

		switch (DATABASE_TYPE)
		{
		case 'MYSQL':
			return "(UNIX_TIMESTAMP({$ds}))";
		break;

		case 'ORACLE':
			return "((to_date({$ds}, 'yyyy-mm-dd hh24:mi:ss') - to_date('19700101', 'yyyymmdd')) * 86400 - to_number(substr(tz_offset(sessiontimezone), 1, 3)) * 3600)";
		break;

		case 'SQLSRV':
			return "(datediff(S, '1970-01-01 00:00:00', {$ds}) - 8 * 3600)";
		break;

		default:
			return "";
		break;
		}
	}


	/**
	 * 2016-12-08����
	 * @note ����ת��Ϊ�ַ����͵ı��ʽ
	 * @param string $f Ҫת�����ֶλ���ʽ
	 * @return string
	 * @note Ӧ��
	 */
	protected function Float2StringFormat($f)
	{
		switch (DATABASE_TYPE)
		{
		case 'MYSQL':
			return "(cast(convert({$f}, decimal(18, 2)) as char))";
		break;

		case 'ORACLE':
			return "(to_char({$f}, 'fm99999990.00'))";
		break;

		case 'SQLSRV':
			return "(cast(convert(decimal(18, 2), {$f}) as char))";
		break;

		default:
			return "";
		break;
		}
	}


	/**
	 * 2016-01-16����
	 * @note ��ȡ��ǰ������ϵͳʱ��(����ʽ)
	 * @param bool $raw �Ƿ񷵻����ݿ���ʽ
	 * @return string
	 * @note Ӧ��
	 */
	public function GetSystemTime($raw = false)
	{
		if ($raw) {
			switch (DATABASE_TYPE) {
				case 'MYSQL':
					return 'now()';
					break;

				case 'ORACLE':
					return 'sysdate';
					break;

				case 'SQLSRV':
					return 'getdate()';
					break;

				default:
					return '';
					break;
			}
		}
		else
			return date('Y-m-d H:i:s');
	}



	/**
	 * @note ��ȡ����ֵ
	 * @param bool $always_local
	 * @return int
	 */
	public function GetErrorCode($always_local = false)
	{
		if ($always_local || null == $this->Database)
		{
			return $this->ErrorCode;
		}
		else
		{
			return $this->Database->GetErrorCode();
		}
	}


	/**
	 * @note ��ȡ������Ϣ
	 * @param bool $always_local
	 * @return mixed|string
	 */
	public function GetErrorInfo($always_local = false)
	{
		if ($always_local || null == $this->Database)
		{
			return $this->ErrorInfo;
		}
		else
		{
			return $this->Database->GetErrorInfo();
		}
	}


	/**
	 * @note �û���Ȩ��Ϣת�û��루�û�id��
	 * @param string $user_auth_token
	 * @return string
	 */
	protected function UserAuthTokenToUserCode($user_auth_token)
	{
		return $user_auth_token;
	}


	/**
	 * @note ����һ���µ�id
	 * @param string $prefix
	 * @return string
	 */
	protected function CreateNewIdent($prefix = '', $md5 = false)
	{
		if (empty($prefix))
		{
			$prefix = 'NEW';
		}

		if ($md5)
		{
			return $prefix . md5(date('YmdHis') . rand(1000, 9999));
		}
		else
		{
			return $prefix . date('YmdHis') . rand(1000, 9999);
		}
	}


	/**
	 * @note �ж�ָ��������, ������û�з��������ļ�¼
	 * @param string $tablename
	 * @param string|array $wheres
	 * @return bool
	 * @auther Ӧ��
	 */
	// DataExists('ims_bigmarket_market', array('app_id' => 123, 'market_id' => 123));
	protected function DataExists($tablename, $wheres)
	{
		$result = $this->PDO_Select($tablename, 'count(1) c', $wheres);
		if (!$result)
		{
			return false;
		}

		return 0 != $result[0]['c'];
	}
}