腓的foreach错误无效参数

Question

我在的foreach在PHP得到这个错误：

在...

代码的foreach（）提供的参数无效：

$database = new PDO('mysql:host=localhost;dbname=staff_tool', $user, ''); 
foreach ($database->query('SELECT id,firstname,lastname FROM `staff` SET categorie_bit = 0') as $testx) { 
       var_dump($testx); 
      } 

编辑代码：

foreach ($database->query('SELECT id,firstname,lastname,categorie_bit FROM `staff` WHERE categorie_bit = 1 SET categorie_bit = 0') as $testx) { 
      var_dump($testx); 
     } 

Answer 1

PHP的foreach期望param之一是一个可迭代的数组，但它似乎像传递一个语句对象（printr）将不会输出更多的选择语句）。你可能会想尝试：

 $stmt = $db->query($sql); 
     $stmt->execute(); 
     $results = $stmt->fetchAll(); 

     foreach($results as $result) 
       var_dump($result); 

Answer 2

$result = $database->query('SELECT id,firstname,lastname,categorie_bit FROM `staff` WHERE categorie_bit = 1 SET categorie_bit = 0'); 

// always check if you have a valid array ... you do not have any guarantees that SELECT query will return you a result set 
if(is_array($result) && count($result) > 0) { 
    foreach ($result as $testx) { 
     var_dump($testx); 
    } 
}