PHP MySQL CRUD Application
What is CRUD
CRUD stands for Create, Read, Update, and Delete. These operations are the fundamental actions for managing data in a database. We've previously covered how to carry out create (i.e., insert), read (i.e., select), update, and delete actions. In this tutorial, we'll build a simple PHP application to perform these operations on a MySQL database table in one place.
Now, let's begin by creating the table that we'll use in all of our examples.
Creating the Database Table
Run the following SQL query to create a table called employees in your MySQL database. We'll use this table for all our subsequent operations.
CREATE TABLE employees (
id INT NOT NULL PRIMARY KEY AUTO_INCREMENT,
name VARCHAR(100) NOT NULL,
address VARCHAR(255) NOT NULL,
salary INT(10) NOT NULL
);
Creating the Config File
Once the table is created, we need to create a PHP script to connect to the MySQL database server. Let's make a file called "config.php" and insert the following code into it.
We'll include this config file in other pages later using the PHP require_once() function.
Example
Procedural Object Oriented PDO
Download
<?php
/* Database credentials. Assuming you are running MySQL
server with default setting (user 'root' with no password) */
define('DB_SERVER', 'localhost');
define('DB_USERNAME', 'root');
define('DB_PASSWORD', '');
define('DB_NAME', 'demo');
/* Attempt to connect to MySQL database */
$link = mysqli_connect(DB_SERVER, DB_USERNAME, DB_PASSWORD, DB_NAME);
// Check connection
if($link === false){
die("ERROR: Could not connect. " . mysqli_connect_error());
}
?>
<?php
/* Database credentials. Assuming you are running MySQL
server with default setting (user 'root' with no password) */
define('DB_SERVER', 'localhost');
define('DB_USERNAME', 'root');
define('DB_PASSWORD', '');
define('DB_NAME', 'demo');
/* Attempt to connect to MySQL database */
$mysqli = new mysqli(DB_SERVER, DB_USERNAME, DB_PASSWORD, DB_NAME);
// Check connection
if($mysqli === false){
die("ERROR: Could not connect. " . $mysqli->connect_error);
}
?>
<?php
/* Database credentials. Assuming you are running MySQL
server with default setting (user 'root' with no password) */
define('DB_SERVER', 'localhost');
define('DB_USERNAME', 'root');
define('DB_PASSWORD', '');
define('DB_NAME', 'demo');
/* Attempt to connect to MySQL database */
try{
$pdo = new PDO("mysql:host=" . DB_SERVER . ";dbname=" . DB_NAME, DB_USERNAME, DB_PASSWORD);
// Set the PDO error mode to exception
$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
} catch(PDOException $e){
die("ERROR: Could not connect. " . $e->getMessage());
}
?>
If you've downloaded the Object Oriented or PDO code examples using the download button, please delete the text "-oo-format" or "-pdo-format" from the file names before running the code.
Note: Change the credentials to match your MySQL server settings before running this code. For instance, replace the database name 'demo' with your own database name, change the username 'root' to your database username, and specify the database password if there is one.
Creating the Landing Page
First, we will create a landing page for our CRUD application that includes a data grid displaying the records from the employees database table. It will also have action icons for each record in the grid, allowing you to view details, update, or delete it.
We'll also add a create button at the top of the data grid for creating new records in the employees table. Create a file named "index.php" and insert the following code into it:
Example
Procedural Object Oriented PDO
Download
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Dashboard</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css">
<script src="https://code.jquery.com/jquery-3.5.1.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/popper.js@1.16.1/dist/umd/popper.min.js"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.min.js"></script>
<style>
.wrapper{
width: 600px;
margin: 0 auto;
}
table tr td:last-child{
width: 120px;
}
</style>
<script>
$(document).ready(function(){
$('[data-toggle="tooltip"]').tooltip();
});
</script>
</head>
<body>
<div class="wrapper">
<div class="container-fluid">
<div class="row">
<div class="col-md-12">
<div class="mt-5 mb-3 clearfix">
<h2 class="pull-left">Employees Details</h2>
<a href="create.php" class="btn btn-success pull-right"><i class="fa fa-plus"></i> Add New Employee</a>
</div>
<?php
// Include config file
require_once "config.php";
// Attempt select query execution
$sql = "SELECT * FROM employees";
if($result = mysqli_query($link, $sql)){
if(mysqli_num_rows($result) > 0){
echo '<table class="table table-bordered table-striped">';
echo "<thead>";
echo "<tr>";
echo "<th>#</th>";
echo "<th>Name</th>";
echo "<th>Address</th>";
echo "<th>Salary</th>";
echo "<th>Action</th>";
echo "</tr>";
echo "</thead>";
echo "<tbody>";
while($row = mysqli_fetch_array($result)){
echo "<tr>";
echo "<td>" . $row['id'] . "</td>";
echo "<td>" . $row['name'] . "</td>";
echo "<td>" . $row['address'] . "</td>";
echo "<td>" . $row['salary'] . "</td>";
echo "<td>";
echo '<a href="read.php?id='. $row['id'] .'" class="mr-3" title="View Record" data-toggle="tooltip"><span class="fa fa-eye"></span></a>';
echo '<a href="update.php?id='. $row['id'] .'" class="mr-3" title="Update Record" data-toggle="tooltip"><span class="fa fa-pencil"></span></a>';
echo '<a href="delete.php?id='. $row['id'] .'" title="Delete Record" data-toggle="tooltip"><span class="fa fa-trash"></span></a>';
echo "</td>";
echo "</tr>";
}
echo "</tbody>";
echo "</table>";
// Free result set
mysqli_free_result($result);
} else{
echo '<div class="alert alert-danger"><em>No records were found.</em></div>';
}
} else{
echo "Oops! Something went wrong. Please try again later.";
}
// Close connection
mysqli_close($link);
?>
</div>
</div>
</div>
</div>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Dashboard</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css">
<script src="https://code.jquery.com/jquery-3.5.1.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/popper.js@1.16.1/dist/umd/popper.min.js"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.min.js"></script>
<style>
.wrapper{
width: 600px;
margin: 0 auto;
}
table tr td:last-child{
width: 120px;
}
</style>
<script>
$(document).ready(function(){
$('[data-toggle="tooltip"]').tooltip();
});
</script>
</head>
<body>
<div class="wrapper">
<div class="container-fluid">
<div class="row">
<div class="col-md-12">
<div class="mt-5 mb-3 clearfix">
<h2 class="pull-left">Employees Details</h2>
<a href="create.php" class="btn btn-success pull-right"><i class="fa fa-plus"></i> Add New Employee</a>
</div>
<?php
// Include config file
require_once "config.php";
// Attempt select query execution
$sql = "SELECT * FROM employees";
if($result = $mysqli->query($sql)){
if($result->num_rows > 0){
echo '<table class="table table-bordered table-striped">';
echo "<thead>";
echo "<tr>";
echo "<th>#</th>";
echo "<th>Name</th>";
echo "<th>Address</th>";
echo "<th>Salary</th>";
echo "<th>Action</th>";
echo "</tr>";
echo "</thead>";
echo "<tbody>";
while($row = $result->fetch_array()){
echo "<tr>";
echo "<td>" . $row['id'] . "</td>";
echo "<td>" . $row['name'] . "</td>";
echo "<td>" . $row['address'] . "</td>";
echo "<td>" . $row['salary'] . "</td>";
echo "<td>";
echo '<a href="read.php?id='. $row['id'] .'" class="mr-3" title="View Record" data-toggle="tooltip"><span class="fa fa-eye"></span></a>';
echo '<a href="update.php?id='. $row['id'] .'" class="mr-3" title="Update Record" data-toggle="tooltip"><span class="fa fa-pencil"></span></a>';
echo '<a href="delete.php?id='. $row['id'] .'" title="Delete Record" data-toggle="tooltip"><span class="fa fa-trash"></span></a>';
echo "</td>";
echo "</tr>";
}
echo "</tbody>";
echo "</table>";
// Free result set
$result->free();
} else{
echo '<div class="alert alert-danger"><em>No records were found.</em></div>';
}
} else{
echo "Oops! Something went wrong. Please try again later.";
}
// Close connection
$mysqli->close();
?>
</div>
</div>
</div>
</div>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Dashboard</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css">
<script src="https://code.jquery.com/jquery-3.5.1.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/popper.js@1.16.1/dist/umd/popper.min.js"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.min.js"></script>
<style>
.wrapper{
width: 600px;
margin: 0 auto;
}
table tr td:last-child{
width: 120px;
}
</style>
<script>
$(document).ready(function(){
$('[data-toggle="tooltip"]').tooltip();
});
</script>
</head>
<body>
<div class="wrapper">
<div class="container-fluid">
<div class="row">
<div class="col-md-12">
<div class="mt-5 mb-3 clearfix">
<h2 class="pull-left">Employees Details</h2>
<a href="create.php" class="btn btn-success pull-right"><i class="fa fa-plus"></i> Add New Employee</a>
</div>
<?php
// Include config file
require_once "config.php";
// Attempt select query execution
$sql = "SELECT * FROM employees";
if($result = $pdo->query($sql)){
if($result->rowCount() > 0){
echo '<table class="table table-bordered table-striped">';
echo "<thead>";
echo "<tr>";
echo "<th>#</th>";
echo "<th>Name</th>";
echo "<th>Address</th>";
echo "<th>Salary</th>";
echo "<th>Action</th>";
echo "</tr>";
echo "</thead>";
echo "<tbody>";
while($row = $result->fetch()){
echo "<tr>";
echo "<td>" . $row['id'] . "</td>";
echo "<td>" . $row['name'] . "</td>";
echo "<td>" . $row['address'] . "</td>";
echo "<td>" . $row['salary'] . "</td>";
echo "<td>";
echo '<a href="read.php?id='. $row['id'] .'" class="mr-3" title="View Record" data-toggle="tooltip"><span class="fa fa-eye"></span></a>';
echo '<a href="update.php?id='. $row['id'] .'" class="mr-3" title="Update Record" data-toggle="tooltip"><span class="fa fa-pencil"></span></a>';
echo '<a href="delete.php?id='. $row['id'] .'" title="Delete Record" data-toggle="tooltip"><span class="fa fa-trash"></span></a>';
echo "</td>";
echo "</tr>";
}
echo "</tbody>";
echo "</table>";
// Free result set
unset($result);
} else{
echo '<div class="alert alert-danger"><em>No records were found.</em></div>';
}
} else{
echo "Oops! Something went wrong. Please try again later.";
}
// Close connection
unset($pdo);
?>
</div>
</div>
</div>
</div>
</body>
</html>
After the employees table is filled with some records, the landing page, which is the CRUD data grid, might look like the picture shown below:
Tip: We've used the Bootstrap framework to quickly and beautifully create the layout for this CRUD application. Bootstrap is a very popular and powerful front-end framework for faster and easier responsive web development. Please check out the Bootstrap tutorial section to learn more about this framework.
Creating the Create Page
In this section, we'll develop the Create functionality of our CRUD application.
Create a file named "create.php" and insert the following code into it. This code will generate a web form for inserting records into the employees table.
Example
Procedural Object Oriented PDO
Download
<?php
// Include config file
require_once "config.php";
// Define variables and initialize with empty values
$name = $address = $salary = "";
$name_err = $address_err = $salary_err = "";
// Processing form data when form is submitted
if($_SERVER["REQUEST_METHOD"] == "POST"){
// Validate name
$input_name = trim($_POST["name"]);
if(empty($input_name)){
$name_err = "Please enter a name.";
} elseif(!filter_var($input_name, FILTER_VALIDATE_REGEXP, array("options"=>array("regexp"=>"/^[a-zA-Z\s]+$/")))){
$name_err = "Please enter a valid name.";
} else{
$name = $input_name;
}
// Validate address
$input_address = trim($_POST["address"]);
if(empty($input_address)){
$address_err = "Please enter an address.";
} else{
$address = $input_address;
}
// Validate salary
$input_salary = trim($_POST["salary"]);
if(empty($input_salary)){
$salary_err = "Please enter the salary amount.";
} elseif(!ctype_digit($input_salary)){
$salary_err = "Please enter a positive integer value.";
} else{
$salary = $input_salary;
}
// Check input errors before inserting in database
if(empty($name_err) && empty($address_err) && empty($salary_err)){
// Prepare an insert statement
$sql = "INSERT INTO employees (name, address, salary) VALUES (?, ?, ?)";
if($stmt = mysqli_prepare($link, $sql)){
// Bind variables to the prepared statement as parameters
mysqli_stmt_bind_param($stmt, "sss", $param_name, $param_address, $param_salary);
// Set parameters
$param_name = $name;
$param_address = $address;
$param_salary = $salary;
// Attempt to execute the prepared statement
if(mysqli_stmt_execute($stmt)){
// Records created successfully. Redirect to landing page
header("location: index.php");
exit();
} else{
echo "Oops! Something went wrong. Please try again later.";
}
}
// Close statement
mysqli_stmt_close($stmt);
}
// Close connection
mysqli_close($link);
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Create Record</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<style>
.wrapper{
width: 600px;
margin: 0 auto;
}
</style>
</head>
<body>
<div class="wrapper">
<div class="container-fluid">
<div class="row">
<div class="col-md-12">
<h2 class="mt-5">Create Record</h2>
<p>Please fill this form and submit to add employee record to the database.</p>
<form action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]); ?>" method="post">
<div class="form-group">
<label>Name</label>
<input type="text" name="name" class="form-control <?php echo (!empty($name_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $name; ?>">
<span class="invalid-feedback"><?php echo $name_err;?></span>
</div>
<div class="form-group">
<label>Address</label>
<textarea name="address" class="form-control <?php echo (!empty($address_err)) ? 'is-invalid' : ''; ?>"><?php echo $address; ?></textarea>
<span class="invalid-feedback"><?php echo $address_err;?></span>
</div>
<div class="form-group">
<label>Salary</label>
<input type="text" name="salary" class="form-control <?php echo (!empty($salary_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $salary; ?>">
<span class="invalid-feedback"><?php echo $salary_err;?></span>
</div>
<input type="submit" class="btn btn-primary" value="Submit">
<a href="index.php" class="btn btn-secondary ml-2">Cancel</a>
</form>
</div>
</div>
</div>
</div>
</body>
</html>
<?php
// Include config file
require_once "config.php";
// Define variables and initialize with empty values
$name = $address = $salary = "";
$name_err = $address_err = $salary_err = "";
// Processing form data when form is submitted
if($_SERVER["REQUEST_METHOD"] == "POST"){
// Validate name
$input_name = trim($_POST["name"]);
if(empty($input_name)){
$name_err = "Please enter a name.";
} elseif(!filter_var($input_name, FILTER_VALIDATE_REGEXP, array("options"=>array("regexp"=>"/^[a-zA-Z\s]+$/")))){
$name_err = "Please enter a valid name.";
} else{
$name = $input_name;
}
// Validate address
$input_address = trim($_POST["address"]);
if(empty($input_address)){
$address_err = "Please enter an address.";
} else{
$address = $input_address;
}
// Validate salary
$input_salary = trim($_POST["salary"]);
if(empty($input_salary)){
$salary_err = "Please enter the salary amount.";
} elseif(!ctype_digit($input_salary)){
$salary_err = "Please enter a positive integer value.";
} else{
$salary = $input_salary;
}
// Check input errors before inserting in database
if(empty($name_err) && empty($address_err) && empty($salary_err)){
// Prepare an insert statement
$sql = "INSERT INTO employees (name, address, salary) VALUES (?, ?, ?)";
if($stmt = $mysqli->prepare($sql)){
// Bind variables to the prepared statement as parameters
$stmt->bind_param("sss", $param_name, $param_address, $param_salary);
// Set parameters
$param_name = $name;
$param_address = $address;
$param_salary = $salary;
// Attempt to execute the prepared statement
if($stmt->execute()){
// Records created successfully. Redirect to landing page
header("location: index.php");
exit();
} else{
echo "Oops! Something went wrong. Please try again later.";
}
}
// Close statement
$stmt->close();
}
// Close connection
$mysqli->close();
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Create Record</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<style>
.wrapper{
width: 600px;
margin: 0 auto;
}
</style>
</head>
<body>
<div class="wrapper">
<div class="container-fluid">
<div class="row">
<div class="col-md-12">
<h2 class="mt-5">Create Record</h2>
<p>Please fill this form and submit to add employee record to the database.</p>
<form action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]); ?>" method="post">
<div class="form-group">
<label>Name</label>
<input type="text" name="name" class="form-control <?php echo (!empty($name_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $name; ?>">
<span class="invalid-feedback"><?php echo $name_err;?></span>
</div>
<div class="form-group">
<label>Address</label>
<textarea name="address" class="form-control <?php echo (!empty($address_err)) ? 'is-invalid' : ''; ?>"><?php echo $address; ?></textarea>
<span class="invalid-feedback"><?php echo $address_err;?></span>
</div>
<div class="form-group">
<label>Salary</label>
<input type="text" name="salary" class="form-control <?php echo (!empty($salary_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $salary; ?>">
<span class="invalid-feedback"><?php echo $salary_err;?></span>
</div>
<input type="submit" class="btn btn-primary" value="Submit">
<a href="index.php" class="btn btn-secondary ml-2">Cancel</a>
</form>
</div>
</div>
</div>
</div>
</body>
</html>
<?php
// Include config file
require_once "config.php";
// Define variables and initialize with empty values
$name = $address = $salary = "";
$name_err = $address_err = $salary_err = "";
// Processing form data when form is submitted
if($_SERVER["REQUEST_METHOD"] == "POST"){
// Validate name
$input_name = trim($_POST["name"]);
if(empty($input_name)){
$name_err = "Please enter a name.";
} elseif(!filter_var($input_name, FILTER_VALIDATE_REGEXP, array("options"=>array("regexp"=>"/^[a-zA-Z\s]+$/")))){
$name_err = "Please enter a valid name.";
} else{
$name = $input_name;
}
// Validate address
$input_address = trim($_POST["address"]);
if(empty($input_address)){
$address_err = "Please enter an address.";
} else{
$address = $input_address;
}
// Validate salary
$input_salary = trim($_POST["salary"]);
if(empty($input_salary)){
$salary_err = "Please enter the salary amount.";
} elseif(!ctype_digit($input_salary)){
$salary_err = "Please enter a positive integer value.";
} else{
$salary = $input_salary;
}
// Check input errors before inserting in database
if(empty($name_err) && empty($address_err) && empty($salary_err)){
// Prepare an insert statement
$sql = "INSERT INTO employees (name, address, salary) VALUES (:name, :address, :salary)";
if($stmt = $pdo->prepare($sql)){
// Bind variables to the prepared statement as parameters
$stmt->bindParam(":name", $param_name);
$stmt->bindParam(":address", $param_address);
$stmt->bindParam(":salary", $param_salary);
// Set parameters
$param_name = $name;
$param_address = $address;
$param_salary = $salary;
// Attempt to execute the prepared statement
if($stmt->execute()){
// Records created successfully. Redirect to landing page
header("location: index.php");
exit();
} else{
echo "Oops! Something went wrong. Please try again later.";
}
}
// Close statement
unset($stmt);
}
// Close connection
unset($pdo);
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Create Record</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<style>
.wrapper{
width: 600px;
margin: 0 auto;
}
</style>
</head>
<body>
<div class="wrapper">
<div class="container-fluid">
<div class="row">
<div class="col-md-12">
<h2 class="mt-5">Create Record</h2>
<p>Please fill this form and submit to add employee record to the database.</p>
<form action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]); ?>" method="post">
<div class="form-group">
<label>Name</label>
<input type="text" name="name" class="form-control <?php echo (!empty($name_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $name; ?>">
<span class="invalid-feedback"><?php echo $name_err;?></span>
</div>
<div class="form-group">
<label>Address</label>
<textarea name="address" class="form-control <?php echo (!empty($address_err)) ? 'is-invalid' : ''; ?>"><?php echo $address; ?></textarea>
<span class="invalid-feedback"><?php echo $address_err;?></span>
</div>
<div class="form-group">
<label>Salary</label>
<input type="text" name="salary" class="form-control <?php echo (!empty($salary_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $salary; ?>">
<span class="invalid-feedback"><?php echo $salary_err;?></span>
</div>
<input type="submit" class="btn btn-primary" value="Submit">
<a href="index.php" class="btn btn-secondary ml-2">Cancel</a>
</form>
</div>
</div>
</div>
</div>
</body>
</html>
The "create.php" file will serve both to display the HTML form and process the submitted form data. It includes basic validation of user inputs (from line 11 to 37) before saving the data.
Creating the Read Page
Next, we'll implement the Read functionality for our CRUD application.
Create a file named "read.php" and insert the following code into it. This code will retrieve records from the employees table based on the employee's id attribute.
Example
Procedural Object Oriented PDO
Download
<?php
// Check existence of id parameter before processing further
if(isset($_GET["id"]) && !empty(trim($_GET["id"]))){
// Include config file
require_once "config.php";
// Prepare a select statement
$sql = "SELECT * FROM employees WHERE id = ?";
if($stmt = mysqli_prepare($link, $sql)){
// Bind variables to the prepared statement as parameters
mysqli_stmt_bind_param($stmt, "i", $param_id);
// Set parameters
$param_id = trim($_GET["id"]);
// Attempt to execute the prepared statement
if(mysqli_stmt_execute($stmt)){
$result = mysqli_stmt_get_result($stmt);
if(mysqli_num_rows($result) == 1){
/* Fetch result row as an associative array. Since the result set
contains only one row, we don't need to use while loop */
$row = mysqli_fetch_array($result, MYSQLI_ASSOC);
// Retrieve individual field value
$name = $row["name"];
$address = $row["address"];
$salary = $row["salary"];
} else{
// URL doesn't contain valid id parameter. Redirect to error page
header("location: error.php");
exit();
}
} else{
echo "Oops! Something went wrong. Please try again later.";
}
}
// Close statement
mysqli_stmt_close($stmt);
// Close connection
mysqli_close($link);
} else{
// URL doesn't contain id parameter. Redirect to error page
header("location: error.php");
exit();
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>View Record</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<style>
.wrapper{
width: 600px;
margin: 0 auto;
}
</style>
</head>
<body>
<div class="wrapper">
<div class="container-fluid">
<div class="row">
<div class="col-md-12">
<h1 class="mt-5 mb-3">View Record</h1>
<div class="form-group">
<label>Name</label>
<p><b><?php echo $row["name"]; ?></b></p>
</div>
<div class="form-group">
<label>Address</label>
<p><b><?php echo $row["address"]; ?></b></p>
</div>
<div class="form-group">
<label>Salary</label>
<p><b><?php echo $row["salary"]; ?></b></p>
</div>
<p><a href="index.php" class="btn btn-primary">Back</a></p>
</div>
</div>
</div>
</div>
</body>
</html>
<?php
// Check existence of id parameter before processing further
if(isset($_GET["id"]) && !empty(trim($_GET["id"]))){
// Include config file
require_once "config.php";
// Prepare a select statement
$sql = "SELECT * FROM employees WHERE id = ?";
if($stmt = $mysqli->prepare($sql)){
// Bind variables to the prepared statement as parameters
$stmt->bind_param("i", $param_id);
// Set parameters
$param_id = trim($_GET["id"]);
// Attempt to execute the prepared statement
if($stmt->execute()){
$result = $stmt->get_result();
if($result->num_rows == 1){
/* Fetch result row as an associative array. Since the result set
contains only one row, we don't need to use while loop */
$row = $result->fetch_array(MYSQLI_ASSOC);
// Retrieve individual field value
$name = $row["name"];
$address = $row["address"];
$salary = $row["salary"];
} else{
// URL doesn't contain valid id parameter. Redirect to error page
header("location: error.php");
exit();
}
} else{
echo "Oops! Something went wrong. Please try again later.";
}
}
// Close statement
$stmt->close();
// Close connection
$mysqli->close();
} else{
// URL doesn't contain id parameter. Redirect to error page
header("location: error.php");
exit();
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>View Record</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<style>
.wrapper{
width: 600px;
margin: 0 auto;
}
</style>
</head>
<body>
<div class="wrapper">
<div class="container-fluid">
<div class="row">
<div class="col-md-12">
<h1 class="mt-5 mb-3">View Record</h1>
<div class="form-group">
<label>Name</label>
<p><b><?php echo $row["name"]; ?></b></p>
</div>
<div class="form-group">
<label>Address</label>
<p><b><?php echo $row["address"]; ?></b></p>
</div>
<div class="form-group">
<label>Salary</label>
<p><b><?php echo $row["salary"]; ?></b></p>
</div>
<p><a href="index.php" class="btn btn-primary">Back</a></p>
</div>
</div>
</div>
</div>
</body>
</html>
<?php
// Check existence of id parameter before processing further
if(isset($_GET["id"]) && !empty(trim($_GET["id"]))){
// Include config file
require_once "config.php";
// Prepare a select statement
$sql = "SELECT * FROM employees WHERE id = :id";
if($stmt = $pdo->prepare($sql)){
// Bind variables to the prepared statement as parameters
$stmt->bindParam(":id", $param_id);
// Set parameters
$param_id = trim($_GET["id"]);
// Attempt to execute the prepared statement
if($stmt->execute()){
if($stmt->rowCount() == 1){
/* Fetch result row as an associative array. Since the result set
contains only one row, we don't need to use while loop */
$row = $stmt->fetch(PDO::FETCH_ASSOC);
// Retrieve individual field value
$name = $row["name"];
$address = $row["address"];
$salary = $row["salary"];
} else{
// URL doesn't contain valid id parameter. Redirect to error page
header("location: error.php");
exit();
}
} else{
echo "Oops! Something went wrong. Please try again later.";
}
}
// Close statement
unset($stmt);
// Close connection
unset($pdo);
} else{
// URL doesn't contain id parameter. Redirect to error page
header("location: error.php");
exit();
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>View Record</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<style>
.wrapper{
width: 600px;
margin: 0 auto;
}
</style>
</head>
<body>
<div class="wrapper">
<div class="container-fluid">
<div class="row">
<div class="col-md-12">
<h1 class="mt-5 mb-3">View Record</h1>
<div class="form-group">
<label>Name</label>
<p><b><?php echo $row["name"]; ?></b></p>
</div>
<div class="form-group">
<label>Address</label>
<p><b><?php echo $row["address"]; ?></b></p>
</div>
<div class="form-group">
<label>Salary</label>
<p><b><?php echo $row["salary"]; ?></b></p>
</div>
<p><a href="index.php" class="btn btn-primary">Back</a></p>
</div>
</div>
</div>
</div>
</body>
</html>
Creating the Update Page
Similarly, we'll implement the Update functionality for our CRUD application.
Create a file named "update.php" and insert the following code into it. This code will update existing records in the employees table based on the employee's id attribute.
Example
Procedural Object Oriented PDO
Download
<?php
// Include config file
require_once "config.php";
// Define variables and initialize with empty values
$name = $address = $salary = "";
$name_err = $address_err = $salary_err = "";
// Processing form data when form is submitted
if(isset($_POST["id"]) && !empty($_POST["id"])){
// Get hidden input value
$id = $_POST["id"];
// Validate name
$input_name = trim($_POST["name"]);
if(empty($input_name)){
$name_err = "Please enter a name.";
} elseif(!filter_var($input_name, FILTER_VALIDATE_REGEXP, array("options"=>array("regexp"=>"/^[a-zA-Z\s]+$/")))){
$name_err = "Please enter a valid name.";
} else{
$name = $input_name;
}
// Validate address address
$input_address = trim($_POST["address"]);
if(empty($input_address)){
$address_err = "Please enter an address.";
} else{
$address = $input_address;
}
// Validate salary
$input_salary = trim($_POST["salary"]);
if(empty($input_salary)){
$salary_err = "Please enter the salary amount.";
} elseif(!ctype_digit($input_salary)){
$salary_err = "Please enter a positive integer value.";
} else{
$salary = $input_salary;
}
// Check input errors before inserting in database
if(empty($name_err) && empty($address_err) && empty($salary_err)){
// Prepare an update statement
$sql = "UPDATE employees SET name=?, address=?, salary=? WHERE id=?";
if($stmt = mysqli_prepare($link, $sql)){
// Bind variables to the prepared statement as parameters
mysqli_stmt_bind_param($stmt, "sssi", $param_name, $param_address, $param_salary, $param_id);
// Set parameters
$param_name = $name;
$param_address = $address;
$param_salary = $salary;
$param_id = $id;
// Attempt to execute the prepared statement
if(mysqli_stmt_execute($stmt)){
// Records updated successfully. Redirect to landing page
header("location: index.php");
exit();
} else{
echo "Oops! Something went wrong. Please try again later.";
}
}
// Close statement
mysqli_stmt_close($stmt);
}
// Close connection
mysqli_close($link);
} else{
// Check existence of id parameter before processing further
if(isset($_GET["id"]) && !empty(trim($_GET["id"]))){
// Get URL parameter
$id = trim($_GET["id"]);
// Prepare a select statement
$sql = "SELECT * FROM employees WHERE id = ?";
if($stmt = mysqli_prepare($link, $sql)){
// Bind variables to the prepared statement as parameters
mysqli_stmt_bind_param($stmt, "i", $param_id);
// Set parameters
$param_id = $id;
// Attempt to execute the prepared statement
if(mysqli_stmt_execute($stmt)){
$result = mysqli_stmt_get_result($stmt);
if(mysqli_num_rows($result) == 1){
/* Fetch result row as an associative array. Since the result set
contains only one row, we don't need to use while loop */
$row = mysqli_fetch_array($result, MYSQLI_ASSOC);
// Retrieve individual field value
$name = $row["name"];
$address = $row["address"];
$salary = $row["salary"];
} else{
// URL doesn't contain valid id. Redirect to error page
header("location: error.php");
exit();
}
} else{
echo "Oops! Something went wrong. Please try again later.";
}
}
// Close statement
mysqli_stmt_close($stmt);
// Close connection
mysqli_close($link);
} else{
// URL doesn't contain id parameter. Redirect to error page
header("location: error.php");
exit();
}
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Update Record</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<style>
.wrapper{
width: 600px;
margin: 0 auto;
}
</style>
</head>
<body>
<div class="wrapper">
<div class="container-fluid">
<div class="row">
<div class="col-md-12">
<h2 class="mt-5">Update Record</h2>
<p>Please edit the input values and submit to update the employee record.</p>
<form action="<?php echo htmlspecialchars(basename($_SERVER['REQUEST_URI'])); ?>" method="post">
<div class="form-group">
<label>Name</label>
<input type="text" name="name" class="form-control <?php echo (!empty($name_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $name; ?>">
<span class="invalid-feedback"><?php echo $name_err;?></span>
</div>
<div class="form-group">
<label>Address</label>
<textarea name="address" class="form-control <?php echo (!empty($address_err)) ? 'is-invalid' : ''; ?>"><?php echo $address; ?></textarea>
<span class="invalid-feedback"><?php echo $address_err;?></span>
</div>
<div class="form-group">
<label>Salary</label>
<input type="text" name="salary" class="form-control <?php echo (!empty($salary_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $salary; ?>">
<span class="invalid-feedback"><?php echo $salary_err;?></span>
</div>
<input type="hidden" name="id" value="<?php echo $id; ?>"/>
<input type="submit" class="btn btn-primary" value="Submit">
<a href="index.php" class="btn btn-secondary ml-2">Cancel</a>
</form>
</div>
</div>
</div>
</div>
</body>
</html>
<?php
// Include config file
require_once "config.php";
// Define variables and initialize with empty values
$name = $address = $salary = "";
$name_err = $address_err = $salary_err = "";
// Processing form data when form is submitted
if(isset($_POST["id"]) && !empty($_POST["id"])){
// Get hidden input value
$id = $_POST["id"];
// Validate name
$input_name = trim($_POST["name"]);
if(empty($input_name)){
$name_err = "Please enter a name.";
} elseif(!filter_var($input_name, FILTER_VALIDATE_REGEXP, array("options"=>array("regexp"=>"/^[a-zA-Z\s]+$/")))){
$name_err = "Please enter a valid name.";
} else{
$name = $input_name;
}
// Validate address address
$input_address = trim($_POST["address"]);
if(empty($input_address)){
$address_err = "Please enter an address.";
} else{
$address = $input_address;
}
// Validate salary
$input_salary = trim($_POST["salary"]);
if(empty($input_salary)){
$salary_err = "Please enter the salary amount.";
} elseif(!ctype_digit($input_salary)){
$salary_err = "Please enter a positive integer value.";
} else{
$salary = $input_salary;
}
// Check input errors before inserting in database
if(empty($name_err) && empty($address_err) && empty($salary_err)){
// Prepare an update statement
$sql = "UPDATE employees SET name=?, address=?, salary=? WHERE id=?";
if($stmt = $mysqli->prepare($sql)){
// Bind variables to the prepared statement as parameters
$stmt->bind_param("sssi", $param_name, $param_address, $param_salary, $param_id);
// Set parameters
$param_name = $name;
$param_address = $address;
$param_salary = $salary;
$param_id = $id;
// Attempt to execute the prepared statement
if($stmt->execute()){
// Records updated successfully. Redirect to landing page
header("location: index.php");
exit();
} else{
echo "Oops! Something went wrong. Please try again later.";
}
}
// Close statement
$stmt->close();
}
// Close connection
$mysqli->close();
} else{
// Check existence of id parameter before processing further
if(isset($_GET["id"]) && !empty(trim($_GET["id"]))){
// Get URL parameter
$id = trim($_GET["id"]);
// Prepare a select statement
$sql = "SELECT * FROM employees WHERE id = ?";
if($stmt = $mysqli->prepare($sql)){
// Bind variables to the prepared statement as parameters
$stmt->bind_param("i", $param_id);
// Set parameters
$param_id = $id;
// Attempt to execute the prepared statement
if($stmt->execute()){
$result = $stmt->get_result();
if($result->num_rows == 1){
/* Fetch result row as an associative array. Since the result set
contains only one row, we don't need to use while loop */
$row = $result->fetch_array(MYSQLI_ASSOC);
// Retrieve individual field value
$name = $row["name"];
$address = $row["address"];
$salary = $row["salary"];
} else{
// URL doesn't contain valid id. Redirect to error page
header("location: error.php");
exit();
}
} else{
echo "Oops! Something went wrong. Please try again later.";
}
}
// Close statement
$stmt->close();
// Close connection
$mysqli->close();
} else{
// URL doesn't contain id parameter. Redirect to error page
header("location: error.php");
exit();
}
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Update Record</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<style>
.wrapper{
width: 600px;
margin: 0 auto;
}
</style>
</head>
<body>
<div class="wrapper">
<div class="container-fluid">
<div class="row">
<div class="col-md-12">
<h2 class="mt-5">Update Record</h2>
<p>Please edit the input values and submit to update the employee record.</p>
<form action="<?php echo htmlspecialchars(basename($_SERVER['REQUEST_URI'])); ?>" method="post">
<div class="form-group">
<label>Name</label>
<input type="text" name="name" class="form-control <?php echo (!empty($name_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $name; ?>">
<span class="invalid-feedback"><?php echo $name_err;?></span>
</div>
<div class="form-group">
<label>Address</label>
<textarea name="address" class="form-control <?php echo (!empty($address_err)) ? 'is-invalid' : ''; ?>"><?php echo $address; ?></textarea>
<span class="invalid-feedback"><?php echo $address_err;?></span>
</div>
<div class="form-group">
<label>Salary</label>
<input type="text" name="salary" class="form-control <?php echo (!empty($salary_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $salary; ?>">
<span class="invalid-feedback"><?php echo $salary_err;?></span>
</div>
<input type="hidden" name="id" value="<?php echo $id; ?>"/>
<input type="submit" class="btn btn-primary" value="Submit">
<a href="index.php" class="btn btn-secondary ml-2">Cancel</a>
</form>
</div>
</div>
</div>
</div>
</body>
</html>
<?php
// Include config file
require_once "config.php";
// Define variables and initialize with empty values
$name = $address = $salary = "";
$name_err = $address_err = $salary_err = "";
// Processing form data when form is submitted
if(isset($_POST["id"]) && !empty($_POST["id"])){
// Get hidden input value
$id = $_POST["id"];
// Validate name
$input_name = trim($_POST["name"]);
if(empty($input_name)){
$name_err = "Please enter a name.";
} elseif(!filter_var($input_name, FILTER_VALIDATE_REGEXP, array("options"=>array("regexp"=>"/^[a-zA-Z\s]+$/")))){
$name_err = "Please enter a valid name.";
} else{
$name = $input_name;
}
// Validate address address
$input_address = trim($_POST["address"]);
if(empty($input_address)){
$address_err = "Please enter an address.";
} else{
$address = $input_address;
}
// Validate salary
$input_salary = trim($_POST["salary"]);
if(empty($input_salary)){
$salary_err = "Please enter the salary amount.";
} elseif(!ctype_digit($input_salary)){
$salary_err = "Please enter a positive integer value.";
} else{
$salary = $input_salary;
}
// Check input errors before inserting in database
if(empty($name_err) && empty($address_err) && empty($salary_err)){
// Prepare an update statement
$sql = "UPDATE employees SET name=:name, address=:address, salary=:salary WHERE id=:id";
if($stmt = $pdo->prepare($sql)){
// Bind variables to the prepared statement as parameters
$stmt->bindParam(":name", $param_name);
$stmt->bindParam(":address", $param_address);
$stmt->bindParam(":salary", $param_salary);
$stmt->bindParam(":id", $param_id);
// Set parameters
$param_name = $name;
$param_address = $address;
$param_salary = $salary;
$param_id = $id;
// Attempt to execute the prepared statement
if($stmt->execute()){
// Records updated successfully. Redirect to landing page
header("location: index.php");
exit();
} else{
echo "Oops! Something went wrong. Please try again later.";
}
}
// Close statement
unset($stmt);
}
// Close connection
unset($pdo);
} else{
// Check existence of id parameter before processing further
if(isset($_GET["id"]) && !empty(trim($_GET["id"]))){
// Get URL parameter
$id = trim($_GET["id"]);
// Prepare a select statement
$sql = "SELECT * FROM employees WHERE id = :id";
if($stmt = $pdo->prepare($sql)){
// Bind variables to the prepared statement as parameters
$stmt->bindParam(":id", $param_id);
// Set parameters
$param_id = $id;
// Attempt to execute the prepared statement
if($stmt->execute()){
if($stmt->rowCount() == 1){
/* Fetch result row as an associative array. Since the result set
contains only one row, we don't need to use while loop */
$row = $stmt->fetch(PDO::FETCH_ASSOC);
// Retrieve individual field value
$name = $row["name"];
$address = $row["address"];
$salary = $row["salary"];
} else{
// URL doesn't contain valid id. Redirect to error page
header("location: error.php");
exit();
}
} else{
echo "Oops! Something went wrong. Please try again later.";
}
}
// Close statement
unset($stmt);
// Close connection
unset($pdo);
} else{
// URL doesn't contain id parameter. Redirect to error page
header("location: error.php");
exit();
}
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Update Record</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<style>
.wrapper{
width: 600px;
margin: 0 auto;
}
</style>
</head>
<body>
<div class="wrapper">
<div class="container-fluid">
<div class="row">
<div class="col-md-12">
<h2 class="mt-5">Update Record</h2>
<p>Please edit the input values and submit to update the employee record.</p>
<form action="<?php echo htmlspecialchars(basename($_SERVER['REQUEST_URI'])); ?>" method="post">
<div class="form-group">
<label>Name</label>
<input type="text" name="name" class="form-control <?php echo (!empty($name_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $name; ?>">
<span class="invalid-feedback"><?php echo $name_err;?></span>
</div>
<div class="form-group">
<label>Address</label>
<textarea name="address" class="form-control <?php echo (!empty($address_err)) ? 'is-invalid' : ''; ?>"><?php echo $address; ?></textarea>
<span class="invalid-feedback"><?php echo $address_err;?></span>
</div>
<div class="form-group">
<label>Salary</label>
<input type="text" name="salary" class="form-control <?php echo (!empty($salary_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $salary; ?>">
<span class="invalid-feedback"><?php echo $salary_err;?></span>
</div>
<input type="hidden" name="id" value="<?php echo $id; ?>"/>
<input type="submit" class="btn btn-primary" value="Submit">
<a href="index.php" class="btn btn-secondary ml-2">Cancel</a>
</form>
</div>
</div>
</div>
</div>
</body>
</html>
Creating the Delete Page
Finally, we'll implement the Delete functionality for our CRUD application.
Create a file named "delete.php" and insert the following code into it. This code will delete existing records from the employees table based on the employee's id attribute.
Example
Procedural Object Oriented PDO
Download
<?php
// Process delete operation after confirmation
if(isset($_POST["id"]) && !empty($_POST["id"])){
// Include config file
require_once "config.php";
// Prepare a delete statement
$sql = "DELETE FROM employees WHERE id = ?";
if($stmt = mysqli_prepare($link, $sql)){
// Bind variables to the prepared statement as parameters
mysqli_stmt_bind_param($stmt, "i", $param_id);
// Set parameters
$param_id = trim($_POST["id"]);
// Attempt to execute the prepared statement
if(mysqli_stmt_execute($stmt)){
// Records deleted successfully. Redirect to landing page
header("location: index.php");
exit();
} else{
echo "Oops! Something went wrong. Please try again later.";
}
}
// Close statement
mysqli_stmt_close($stmt);
// Close connection
mysqli_close($link);
} else{
// Check existence of id parameter
if(empty(trim($_GET["id"]))){
// URL doesn't contain id parameter. Redirect to error page
header("location: error.php");
exit();
}
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Delete Record</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<style>
.wrapper{
width: 600px;
margin: 0 auto;
}
</style>
</head>
<body>
<div class="wrapper">
<div class="container-fluid">
<div class="row">
<div class="col-md-12">
<h2 class="mt-5 mb-3">Delete Record</h2>
<form action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]); ?>" method="post">
<div class="alert alert-danger">
<input type="hidden" name="id" value="<?php echo trim($_GET["id"]); ?>"/>
<p>Are you sure you want to delete this employee record?</p>
<p>
<input type="submit" value="Yes" class="btn btn-danger">
<a href="index.php" class="btn btn-secondary">No</a>
</p>
</div>
</form>
</div>
</div>
</div>
</div>
</body>
</html>
<?php
// Process delete operation after confirmation
if(isset($_POST["id"]) && !empty($_POST["id"])){
// Include config file
require_once "config.php";
// Prepare a delete statement
$sql = "DELETE FROM employees WHERE id = ?";
if($stmt = $mysqli->prepare($sql)){
// Bind variables to the prepared statement as parameters
$stmt->bind_param("i", $param_id);
// Set parameters
$param_id = trim($_POST["id"]);
// Attempt to execute the prepared statement
if($stmt->execute()){
// Records deleted successfully. Redirect to landing page
header("location: index.php");
exit();
} else{
echo "Oops! Something went wrong. Please try again later.";
}
}
// Close statement
$stmt->close();
// Close connection
$mysqli->close();
} else{
// Check existence of id parameter
if(empty(trim($_GET["id"]))){
// URL doesn't contain id parameter. Redirect to error page
header("location: error.php");
exit();
}
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Delete Record</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<style>
.wrapper{
width: 600px;
margin: 0 auto;
}
</style>
</head>
<body>
<div class="wrapper">
<div class="container-fluid">
<div class="row">
<div class="col-md-12">
<h2 class="mt-5 mb-3">Delete Record</h2>
<form action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]); ?>" method="post">
<div class="alert alert-danger">
<input type="hidden" name="id" value="<?php echo trim($_GET["id"]); ?>"/>
<p>Are you sure you want to delete this employee record?</p>
<p>
<input type="submit" value="Yes" class="btn btn-danger">
<a href="index.php" class="btn btn-secondary ml-2">No</a>
</p>
</div>
</form>
</div>
</div>
</div>
</div>
</body>
</html>
<?php
// Process delete operation after confirmation
if(isset($_POST["id"]) && !empty($_POST["id"])){
// Include config file
require_once "config.php";
// Prepare a delete statement
$sql = "DELETE FROM employees WHERE id = :id";
if($stmt = $pdo->prepare($sql)){
// Bind variables to the prepared statement as parameters
$stmt->bindParam(":id", $param_id);
// Set parameters
$param_id = trim($_POST["id"]);
// Attempt to execute the prepared statement
if($stmt->execute()){
// Records deleted successfully. Redirect to landing page
header("location: index.php");
exit();
} else{
echo "Oops! Something went wrong. Please try again later.";
}
}
// Close statement
unset($stmt);
// Close connection
unset($pdo);
} else{
// Check existence of id parameter
if(empty(trim($_GET["id"]))){
// URL doesn't contain id parameter. Redirect to error page
header("location: error.php");
exit();
}
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Delete Record</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<style>
.wrapper{
width: 600px;
margin: 0 auto;
}
</style>
</head>
<body>
<div class="wrapper">
<div class="container-fluid">
<div class="row">
<div class="col-md-12">
<h2 class="mt-5 mb-3">Delete Record</h2>
<form action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]); ?>" method="post">
<div class="alert alert-danger">
<input type="hidden" name="id" value="<?php echo trim($_GET["id"]); ?>"/>
<p>Are you sure you want to delete this employee record?</p>
<p>
<input type="submit" value="Yes" class="btn btn-danger">
<a href="index.php" class="btn btn-secondary ml-2">No</a>
</p>
</div>
</form>
</div>
</div>
</div>
</div>
</body>
</html>
Creating the Error Page
Finally, let's create one more file named "error.php". This page will be displayed if the request is invalid, for example, if the id parameter is missing from the URL query string or is not valid.
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Error</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<style>
.wrapper{
width: 600px;
margin: 0 auto;
}
</style>
</head>
<body>
<div class="wrapper">
<div class="container-fluid">
<div class="row">
<div class="col-md-12">
<h2 class="mt-5 mb-3">Invalid Request</h2>
<div class="alert alert-danger">Sorry, you've made an invalid request. Please <a href="index.php" class="alert-link">go back</a> and try again.</div>
</div>
</div>
</div>
</div>
</body>
</html>
After a long journey, we have completed our CRUD application using PHP and MySQL. We recommend you to start from the beginning of the PHP & MySQL database tutorial section if you haven't already, to better understand each part of this tutorial.
