警告：mysql_fetch_assoc（）期望参数1是资源，在chat.php [duplicate]中给出boolean

Question

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• mysql_fetch_array()/mysql_fetch_assoc()/mysql_fetch_row()/mysql_num_rows etc… expects parameter 1 to be resource or result 32 answers

I am developing a Chat Application. When I try to run the website, I get the error:

Warning: mysql_fetch_assoc() expects parameter 1 to be resource, boolean given in chat.php

PHP:

function get_msg()
{
    $query = "SELECT 'sender','message' FROM 'chat'.'chat' ";
    $run=mysql_query($query);
    $messages = array();
    while ($message = mysql_fetch_assoc($run))
    {
        $messages[]=array('sender'=>$message['Sender'],'message'=>$message['Message']);
    }
    return $messages;
}

</div>

Answer 1

Wrong quotes:

$query = "SELECT 'sender','message' FROM 'chat'.'chat' ";
                 ^------^-^-------^------^----^-^----^--- *ALL* wrong

None of those need to be quoted.