SQLSTATE [HY000]：一般错误和array（0）{}

Question

In my pdo script, I was querying my database to give me all the users in my database in my local machine but all I see is "SQLSTATE[HY000]: General error"

Here is my script;

<?php
ini_set('display_errors','on');
require_once('connect.php');

try{

$username='charlyo';
$con=$connect->query('select * from users where username=:username');
var_dump($con->fetchAll());
}
catch(PDOException $e){
   echo $e->getMessage();

}

 ?>

and while trouble-shooting it I tried to use prepared statements. I now get "array(0){}" without returning any arrays while I used fetchAll method.

Here is the second script of prepared statement:

<?php
ini_set('display_errors','on');
require_once('connect.php');

try{

$username='charlyo';
$con=$connect->prepare('select * from users where username=:username');
$con->bindParam(':username',$username);
$con->execute();
var_dump($con->fetchAll());
}
catch(PDOException $e){
   echo $e->getMessage();

}

 ?>

Answer 1

You should also post the contents of the file connect.php , so we can be sure of how you are instantiating the PDO object (make sure to remove the passwords).

Stacked queries (multiples queries separated by a ; ) are not supported by default in PDO, the emulation mode has to be enabled ( PDO::ATTR_EMULATE_PREPARES ) but it's not really needed in your case.

In order to make your second example work, you should just remove the use charles; part and make sure to pass dbname=charles in the DSN that you are providing to PDO's constructor.

Answer 2

Remove use charles; from query. I am not sure why you have used it but take it off from query and check.