In the previous section, we have learned how to insert data into database from a PHP script. Now, we'll see how we can insert data into database obtained from an HTML form. Let's create an HTML form that can be used to insert new records to persons table.

Step 1: Creating the HTML Form

Here's a simple HTML form that has three text <input> fields and a submit button.

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Add Record Form</title>
</head>
<body>
<form action="insert.php" method="post">
<p>
<label for="firstName">First Name:</label>
<input type="text" name="first_name" id="firstName">
</p>
<p>
<label for="lastName">Last Name:</label>
<input type="text" name="last_name" id="lastName">
</p>
<p>
<label for="emailAddress">Email Address:</label>
<input type="text" name="email" id="emailAddress">
</p>
<input type="submit" value="Submit">
</form>
</body>
</html>

Step 2: Retrieving and Inserting the Form Data

When a user clicks the submit button of the add record HTML form, in the example above, the form data is sent to 'insert.php' file. The 'insert.php' file connects to the MySQL database server, retrieves forms fields using the PHP $_REQUEST variables and finally execute the insert query to add the records. Here is the complete code of our 'insert.php' file:

<?php
/* Attempt MySQL server connection. Assuming you are running MySQL
server with default setting (user 'root' with no password) */
$link = mysqli_connect("localhost", "root", "", "demo");

// Check connection
if($link === false){
die("ERROR: Could not connect. " . mysqli_connect_error());
}

// Escape user inputs for security
$first_name = mysqli_real_escape_string($link, $_REQUEST['first_name']);
$last_name = mysqli_real_escape_string($link, $_REQUEST['last_name']);
$email = mysqli_real_escape_string($link, $_REQUEST['email']);

// attempt insert query execution
$sql = "INSERT INTO persons (first_name, last_name, email) VALUES ('$first_name', '$last_name', '$email')";
if(mysqli_query($link, $sql)){
echo "Records added successfully.";
} else{
echo "ERROR: Could not able to execute $sql. " . mysqli_error($link);
}

// close connection
mysqli_close($link);
?>

This is very basic example of inserting the form data in a MySQL database table. You can extend this example and make it more interactive by adding validations to the user inputs before inserting it to the database tables. Please check out the tutorial on PHP form validation to learn more about sanitizing and validating user inputs using PHP.