dongzhuang6247 2019-08-16 19:20
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This question already has an answer here:

I understand that this error occurs when you try to call a method on something that is not an object. In this case, the variable that should hold an object is actually a boolean.

I just don't know how to fix it.

If you look at MySQL::query(), the function returns either false (on error) or an object of the type mysql_result. A bad SQL query will make the query fail and the function to return false.

Because the error occurs when I try to call setFetchMode, it probably means my PDO query failed, but I honestly have no idea.


$host = 'localhost';
$dbname = 'DBNAME';
$username = 'USERNAME';
$password = 'PASSWORD';

try {

   $pdo = new PDO("mysql:host=$host;dbname=$dbname", $username, $password);

   $sql = 'SELECT id, topic, category, type, doi, author, year
   FROM literature
   ORDER BY id';

   $q = $pdo->query($sql);


} catch (PDOException $e) {

   die("Could not connect to the database $dbname :" . $e->getMessage());



It returns the error: "PHP Fatal error: Uncaught Error: Call to a member function setFetchMode() on boolean in /root/somewhere/somefile/anotherfile/FILENAME.php:12" because $q is false. I just don't know how to have it return the object.

The weird part is that it works perfectly fine on my stand-alone server.

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  • duanban4769 2019-08-16 19:59

    if your $q is false its mean you have error in sql query or a connection, you can use this connection to see more info about your error:

    $pdo = new PDO("mysql:host=$host;dbname=$dbname", $username, $password, [PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION]);

    then it will throw exception before you try to access (bool)->{someMethod}

    本回答被题主选为最佳回答 , 对您是否有帮助呢?



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