mysql_num_rows error

i keep getting this everytime i type a russian word in my translator

Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource in E:\webareas\cm541\translation.php on line 28


the code being

<?
$trans = $_POST["translate"];

include("connection.php");
$connection = @mysql_connect($db_host, $db_user, $db_password) or die("Error Connecting");
mysql_select_db($db_name, $connection);

$query = "select* FROM Dictionary where russian ='$trans'";
$result= mysql_query($query, $connection);
$num_rows = mysql_num_rows($result);
for ($i =0; $i< mysql_num_rows($result); $i++)



{
$english = mysql_result($result, $i, "english");
$russian = mysql_result($result, $i, "russian");

echo '<tr>
<td width="550" height="30"align="center" valign="middle"><a href="'.$english.'?page=">'.$english.'/'.$russian.'</a></td>
</tr>';

}

?>

 

the problem is that your resultset returned from the query is invalid

try changing:

$result= mysql_query($query, $connection);
$num_rows = mysql_num_rows($result);
for ($i =0; $i< mysql_num_rows($result); $i++)

Code (markup):

to

$result= mysql_query($query, $connection);
if($result) {
  $num_rows = mysql_num_rows($result);
  for ($i =0; $i< mysql_num_rows($result); $i++)
  ...
}
else {
  // code for not valid resultset - e.g. use the msql_error() function here
}

Code (markup):

 

Shouldn't this:

be like this:

?

 

Actually, it works both ways, although this is technically the correct way to do it if not concatenating:

$query = "select * FROM Dictionary where russian ='{$trans}'";

PHP:

I see a couple of things wrong with your code. First, you don't sanitize your user input, leaving you open to SQL injection. You need to change this:

$trans = $_POST["translate"];

PHP:

to this:

$trans = mysql_real_escape_string($_POST["translate"]);

PHP:

You should probably validate it too, but this should be enough. Also, using mysql_result is inefficient if you are retrieving data from more than one field. Change this:

$num_rows = mysql_num_rows($result);
for ($i =0; $i< mysql_num_rows($result); $i++)
{
$english = mysql_result($result, $i, "english");
$russian = mysql_result($result, $i, "russian");

echo '<tr>
<td width="550" height="30"align="center" valign="middle"><a href="'.$english.'?page=">'.$english.'/'.$russian.'</a></td>
</tr>';

}

PHP:

to this:

while($row=@mysql_fetch_assoc($result))
{
echo '<tr>
<td width="550" height="30"align="center" valign="middle"><a href="'.$row['english'].'?page=">'.$row['english'].'/'.$row['russian'].'</a></td>
</tr>';
}

PHP:

If you are only pulling two fields out of your table, you can optimize your query by changing it to this:

$query = "select english,russian FROM Dictionary where russian ='{$trans}'";

PHP:

Are the Russian characters in Cyrillic or Roman characters? Using the wrong character set may be causing the error you are seeing.

 

Try:


$result = mysql_query($query, $connection) or die(mysql_error());