PHP pdao用法总结

$sql = 'SELECT name, colour, calories
    FROM fruit
    WHERE calories < :calories AND colour = :colour';
$sth = $dbh->prepare($sql, array(PDO::ATTR_CURSOR => PDO::CURSOR_FWDONLY));
$sth->execute(array(':calories' => 150, ':colour' => 'red'));
$red = $sth->fetchAll();
$sth->execute(array(':calories' => 175, ':colour' => 'yellow'));
$yellow = $sth->fetchAll();

$sth = $dbh->prepare('SELECT name, colour, calories
    FROM fruit
    WHERE calories < ? AND colour = ?');
$sth->execute(array(150, 'red'));
$red = $sth->fetchAll();
$sth->execute(array(175, 'yellow'));
$yellow = $sth->fetchAll();

总结地址：http://www.cnblogs.com/pinocchioatbeijing/archive/2012/03/20/2407869.html

http://sjolzy.cn/PDO-query-results-achieved-in-many-ways.html

无论原来数据库里的数据是什么类型，通过这写遍历方法出来的数组，里面的成员都成了字符串？ var_dump一下，发现全是string......

If you want to use PDO::FETCH_CLASS but don't like that all the values are of the type string, you can always use the __construct function of the class specified to convert them to a different type.

Another way is using mysqlnd, but it seems I had to recompile PHP for that.

<?php

class Cdr {
public $a; // int
  public $b; // float
  public $c; // string

  public function __construct() {
  $this->a = intval($this->a);
  $this->b = floatval($this->b);
}

}

// ...
$arrCdrs = $objSqlStatement->fetchAll(PDO::FETCH_CLASS, 'Cdr');

?>

setAttribute(PDO::ATTR_EMULATE_PREPARES, false);

发现填上这句话后，fetchall得来的类型是正确的。

如果没有这句话，fetchall得来的都是字符串

PDO 指南

http://www.oschina.net/translate/php-pdo-how-to