PHP Site Search Implementation Guide: From Form Submission to Database Query

Introduction to PHP Site Search

As website content grows, offering users an efficient way to find information becomes increasingly important. A site search feature can greatly enhance both usability and the overall user experience. This tutorial walks you through implementing a basic search function using PHP.

Building the Search Form

Start by creating a front-end form that allows users to input their search terms:

<form method="GET" action="search.php">
  <input type="text" name="keyword" placeholder="Enter keywords">
  <input type="submit" value="Search">
</form>

This form uses the GET method to pass the user’s keyword to the results page (search.php) via the URL.

Processing the Search Request

In search.php, the first step is to retrieve the submitted keyword:

<?php
$keyword = $_GET['keyword'];
// Connect to database and perform the query
// ...
?>

Here, the user input is accessed using $_GET. This keyword will be used to search relevant content from the database.

Connecting to the Database and Querying

Use PDO to establish a connection and execute a query with basic keyword matching:

<?php
$keyword = $_GET['keyword'];

$host = 'localhost';
$dbname = 'database_name';
$username = 'username';
$password = 'password';

try {
  $db = new PDO("mysql:host=$host;dbname=$dbname", $username, $password);
} catch (PDOException $e) {
  die("Database connection failed: " . $e->getMessage());
}

$query = "SELECT * FROM articles WHERE title LIKE '%$keyword%' OR content LIKE '%$keyword%'";
$result = $db->query($query);
$articles = $result->fetchAll(PDO::FETCH_ASSOC);
?>

This query uses the LIKE operator to perform a fuzzy search in both the title and content fields of the articles table.

Displaying Search Results

Loop through the results and output them in HTML:

<?php
foreach ($articles as $article) {
  echo '<h3>' . $article['title'] . '</h3>';
  echo '<p>' . $article['content'] . '</p>';
}
?>

This way, users can see all articles that contain the searched keyword in the title or content.

Improving the Search Experience

While this is a functional and simple example, real-world applications may require enhancements such as:

• Sanitizing user input to prevent SQL injection
• Adding pagination to handle large result sets
• Using word segmentation for better accuracy in languages like Chinese
• Integrating full-text search engines like ElasticSearch or Sphinx for performance and scalability

Optimizing your search functionality helps deliver a better user experience and can also improve engagement and conversions.

Conclusion

This tutorial covered the fundamental steps for building a basic site search feature using PHP, from form submission to database querying and rendering results. Although the example is simple, it provides a strong foundation for beginners. You can expand upon it based on your project needs with more advanced logic and tools.