how to fix this query error

[simon2x1]

Warning: mysql_fetch_ass oc(): supplied argument is not a valid MySQL result resource in C:\wamp\www\blo g\blogpost.php on line 11
how can i fix thes error above this is my code

<?php
 class BlogPost  
 {  
public $id;  
 public $title;  
 public $post;  
 public $author;
 if (!empty($inAuthorId))  
     {  
         $result = mysql_query("SELECT first_name, last_name FROM people WHERE id = " . $inAuthorId);  
         $row = mysql_fetch_assoc($result);  
		$this->author = $row["first_name"] . " " . $row["last_name"];  
     }
} 
?>

[JKing]

There could be several reasons for this.

Have you connected to the mysql server and selected your database?

Are you using the right field and table names?

Modify your code as follows to get some more information on why the query is failing.

<?php
 class BlogPost  
 {  
public $id;  
 public $title;  
 public $post;  
 public $author;
 if (!empty($inAuthorId))  
     {  
         $result = mysql_query("SELECT first_name, last_name FROM people WHERE id = " . $inAuthorId) or die(mysql_error());  
         $row = mysql_fetch_assoc($result);  
        $this->author = $row["first_name"] . " " . $row["last_name"];  
     }
} 
?>