Mysql Error

kanika

Hello'
I'm using following code and getting mysqlerror
Warning: mysql_num_rows() expects parameter 1 to be resource, boolean given in C:\xampp\htdocs/.....
Code is
$query="SELECT ('$retfield') FROM ('$table') WHERE ('$givefield')=('$val')";
$res=mysql_query($query);
if(mysql_num_rows($res) > 0){
}

Upto my knowledge I'm using correct syntax bt I dnt where I'm going wrong.
Can anyone help me?

halojoy

When num_rrows give such an error
it means the query failed.
Most often because a syntax error in query.

I will have guess at what is your correct query.
And I will add [man]mysql_error[/man]
so that MySQL will give a hint where you have the syntax issue.

$query = "SELECT $retfield FROM $table WHERE $givefield='$val'";
$res = mysql_query($query);
// check if there was an error executing the query
if(!$res){
    echo 'Your QUERY: ' . $query . '<br />MySQL error: ' . mysql_error();
}

if(mysql_num_rows($res) > 0){
}

kanika

Thanx a lot it works