Why this error "Trying to get property 'num_rows' of non-object"

Trying to get property 'num_rows' of non-object error

Mistake!

You are trying to use the property 'num_rows' while $result is not an object here

Solutions:

1. Query execution:

Execute query before checking row count

$sql->execute();

Your code can be like:

// Query 
$query = "SELECT * FROM table_name WHERE column = 'value'";

// Preparation
$sql = $conn->prepare($query);

//Execution
$sql->execute();

// Get result 
$result = $sql->get_result();

// Check number of rows
if ($result->num_rows > 0) {
       $result = $result->fetch_assoc();
        // your php code here
  }

2. Recommended query:

// Query 
$query = "SELECT * FROM table_name WHERE column = 'value'";

$result = mysqli_query($conn, $query);

// Check number of rows
if ($result->num_rows > 0) {
$result = $result->fetch_assoc();
print_r($result);
// your php code here
}