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1.在學(xué)習(xí)php時(shí)用PDO模式連接數(shù)據(jù)庫(kù)，查詢數(shù)據(jù)時(shí)，在調(diào)用fetch方法時(shí)出現(xiàn)錯(cuò)誤：Fatal error: Call to a member function fetch() on a non-object
2.代碼

//PDO連接數(shù)據(jù)庫(kù)方式
     try{
         $db_conn = new PDO('mysql:host = localhost;dbname = test','root','123456');
         echo "連接成功！";
     }
     catch(PDOException $e){
         echo "Could not connect to datebase";
     }

//從表中選取數(shù)據(jù)
     $stmt = $db_conn->query('SELECT * FROM user');
     var_dump($stmt);
//顯示結(jié)果
     while ($row = $stmt->fetch()) {
         echo $row['name'].$row['number'].$row['class'];
     }

3.錯(cuò)誤結(jié)果

4.數(shù)據(jù)庫(kù)