==============================================================
CTblHist から　CDDriver へコード移転 [1]
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class CTblHist extends CTblBase {

	const TBL_NAME = "hist";
	const ID_NAME = "hist_id";

	public function __construct( $prt ) {
		parent::__construct( $prt );

=>		$cfg = CEnv::config("poll/block");
=>		$this->sig_expire = $this->getSigExpire($cfg);
	}

=>	private function getSigExpire( $cfg ) {
=>		if ( empty($cfg["sig-expire"]) ) { return 0; }
=>		$days = $cfg["sig-expire"];
=>		return ( substr($days,-1) == "s" ) ?
=>			intval(substr($days,0,-1)) :
=>			intval($days)*(60*60*24);
=>	}
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add "getSigExpireInterval" to CDDriver

class CDDriver {

	public function getSigExpireInterval() {
		$cfg = CEnv::config("poll/block");
		if ( empty($cfg["sig-expire"]) ) { return 0; }
		$days = $cfg["sig-expire"];
		return ( substr($days,-1) == "s" ) ?
			intval(substr($days,0,-1)) :
			intval($days)*(60*60*24);
	}

}
==============================================================
CTblHist から　CDDriver へコード移転 [2]
--------------------------------------------------------------
	public function expire( $data ) {
=>		if ( $this->sig_expire <= 0 ) { return; }

=>		$now = $this->prt->getDateTime();
=>		$str_limit = $this->prt->getDateTimeStr($now-$this->sig_expire);

		//-- delete expired records
		$clx = array();
		$clx[] = CSql::clDelete(self::TBL_NAME);
		$cond = array();
		$cond[] = CSql::clCond("dt_create","<",$str_limit);
		$clx[] = CSql::clWhere("AND",$cond);
		CSql::query($clx);
	}
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	public function expire( $data, $threshold ) {
		$clx = array();
		$clx[] = CSql::clDelete(self::TBL_NAME);
		$cond = array();
		$cond[] = CSql::clCond("dt_create","<",$threshold);
		$clx[] = CSql::clWhere("AND",$cond);
		CSql::query($clx);
	}
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modify "expire" of CDDriver
add "getSigExpireThreshold" to CDDriver

class CDDriver {

	public function expire( $data ) {
		$threshold = $this->getSigExpireThreshold();
		if ( is_null($threshold) ) { return; }
		$this->tbl_hist->expire($data,$threshold);
	}

	public function getSigExpireThreshold() {
		$interval = $this->getSigExpireInterval();
		if ( $interval <= 0 ) { return null; }
		$now = $this->getDateTime();
		return $this->getDateTimeStr($now-$interval);
	}

}
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modify "expire" of CDDriver
add "expire" to CTblVoter

class CDDriver {

	public function expire( $data ) {
		$threshold = $this->getSigExpireThreshold();
		if ( is_null($threshold) ) { return; }
		$this->tbl_hist->expire($data,$threshold);
		$this->tbl_voter->expire($data,$threshold);
	}

}

class CTblVoter extends CTblBase {

	public function getSigExpireThreshold() {
		$interval = $this->getSigExpireInterval();
		if ( $interval <= 0 ) { return null; }
		$now = $this->getDateTime();
		return $this->getDateTimeStr($now-$interval);
	}

}
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add "expiration threshold" code to CTblVoter::findVoter
add "expiration threshold" code to CTblHist::loadSelsx and CTblHist::loadSels

		//-- expiration threshold
		$threshold = $this->prt->getSigExpireThreshold();
		if ( !is_null($threshold) ) {
			$cond[] = CSql::clCond("dt_create",">=",$threshold);
		}

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驚くべきことに、CTblVoterは、最初のバージョンから、投票ごとにdt_createをアップデートしている。