What are some potential pitfalls of allowing users to input free-form text in a database column intended for numerical values, as seen in the PHP forum thread?

Allowing users to input free-form text in a database column intended for numerical values can lead to data integrity issues and potential errors when performing calculations or queries. To solve this issue, you can validate user input to ensure it is a valid numerical value before inserting it into the database.

// Validate user input as a numerical value before inserting into the database
$input = $_POST['input'];
if (is_numeric($input)) {
    // Insert the numerical value into the database
    $query = "INSERT INTO table_name (numerical_column) VALUES ($input)";
    // Execute the query
} else {
    // Handle the case where the input is not a valid numerical value
    echo "Invalid input. Please enter a numerical value.";
}