dynamic search form

[weazy]

i have users search through a database using a form. no one field is required, but any can be used.

i am trying to kick the results to a the num_rows() array and then echo to determine whether the script is getting anything back from database. i get the folllowing error:
mysql_num_rows(): supplied argument is not a valid MySQL result resource

here is the code:

$query = "select * from products where ";

$parameterStr = "";

if ($productname != "")
{

$parameterStr="productname LIKE '%$productname%' ";

}

if ($sku != "")
{

if ($parameterStr == "")
{

  $parameterStr = "sku == $sku";
}
  else
{
  $parameterStr = $parameterStr." AND sku == $sku ";
} 

}

if ($catID !="")
{

if ($parameterStr == "")
{

  $parameterStr = "catID == $catID";
}
  else
{
  $parameterStr = $parameterStr." AND catID == $catID ";
} 

}

if ($vendorID != "")
{

if ($parameterStr=="")
{

  $parameterStr="vendorID == $vendorID ";
}
  else
{
  $parameterStr=$parameterStr." AND vendorID == $vendorID ";
} 

}

$query = $query.$parameterStr;

$myquery = mysql_query($query);

$num_results = mysql_num_rows($myquery);

echo $num_results;

thanks for the input

[bad76]

Hi
can you add some line of debug?

Try this and check the result:

$query = $query.$parameterStr; 
$myquery = mysql_query($query) or die("Error on query:".mysql_error()."<br><i>".$query."</i>");


$num_results = mysql_num_rows($myquery); 

echo $num_results; 

[weazy]

it was the use of == rather than =