Advertencia: mysqli_num_rows () espera que el parámetro 1 sea mysqli_result, bool dado en
// warning: mysqli_num_rows() expects parameter 1 to be mysqli_result, bool given in,
//this error will get mostly when query not giving any return value or having some error in query
$con=mysqli_connect("localhost","root","","employeeDB");
$sql="select * from employee where id = 1";
if ($result=mysqli_query($con,$sql)){
// this will return the number of rows in result set
$numRos=mysqli_num_rows($result);
if($numRos > 0){
$data = mysqli_fetch_array($result);
print_r($data);
}else{
print "No data found";
}
}
mysqli_close($con);
@CodeGrepperManu