PHP AJAX Live Search Example

PHP AJAX Live Search Example

AJAX Live Search allows users to search data in real time as they type—without reloading the page.
This is very common in search boxes, user lookup, product search, admin panels, etc.

What is AJAX Live Search?

User types in input box
AJAX sends request on each key press
PHP fetches matching data
Results appear instantly below input

Also called Autocomplete / Instant Search

How It Works (Flow)

User types text
JavaScript sends AJAX request
PHP queries database
Matching records returned
HTML updates dynamically

Database Table (Example)

`students` table

Sample data:

HTML + JavaScript (AJAX)

`index.html`

<!DOCTYPE html>
<html>
<head>
<title>PHP AJAX Live Search</title>

<script>
function liveSearch(str) {
if (str.length == 0) {
document.getElementById("result").innerHTML = "";
return;
}

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function () {
if (xhr.readyState == 4 && xhr.status == 200) {
document.getElementById("result").innerHTML = xhr.responseText;
}
};

xhr.open("GET", "search.php?q=" + str, true);
xhr.send();
}
</script>
</head>

<body>
<h2>Live Search (AJAX + PHP)</h2>

<input type="text" placeholder="Search name..."
onkeyup="liveSearch(this.value)">

<div id="result"></div>
</body>
</html>

<!DOCTYPE html>

<html>

<head>

<title>PHP AJAX Live Search</title>

function liveSearch(str) {

if (str.length == 0) {

document.getElementById("result").innerHTML = "";

return;

}

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function () {

if (xhr.readyState == 4 && xhr.status == 200) {

document.getElementById("result").innerHTML = xhr.responseText;

}

};

xhr.open("GET", "search.php?q=" + str, true);

xhr.send();

}

</script>

</head>

<body>

<h2>Live Search (AJAX + PHP)</h2>

<input type="text" placeholder="Search name..."

onkeyup="liveSearch(this.value)">

</body>

</html>

PHP File (Search Logic)

`search.php`

<?php
$conn = mysqli_connect("localhost", "root", "", "test");

$q = $_GET['q'];

$sql = "SELECT name FROM students WHERE name LIKE '$q%'";
$result = mysqli_query($conn, $sql);

if (mysqli_num_rows($result) > 0) {
echo "<ul>";
while ($row = mysqli_fetch_assoc($result)) {
echo "<li>" . $row['name'] . "</li>";
}
echo "</ul>";
} else {
echo "No result found";
}
?>

<?php

$conn = mysqli_connect("localhost", "root", "", "test");

$q = $_GET['q'];

$sql = "SELECT name FROM students WHERE name LIKE '$q%'";

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

if (mysqli_num_rows($result) > 0) {

echo "<ul>";

while ($row = mysqli_fetch_assoc($result)) {

echo "<li>" . $row['name'] . "</li>";

}

echo "</ul>";

} else {

echo "No result found";

}

% → wildcard
$q% → starts with typed text

Output Example

Typing “Ra” shows:

No page reload
Real-time results

Improve Search (Anywhere Match)

Matches text anywhere in the name

Security Improvement (Interview)

Use Prepared Statements to prevent SQL Injection.

Common Mistakes

Query on every keystroke without limit
No input validation
SQL injection risk
Not handling empty input
No index on searched column

AJAX Live Search vs Normal Search

Feature	Live Search	Normal Search
Page reload	No	Yes
User experience	Fast	Slower
Server calls	More	Less
Modern apps	Yes	Old

Interview Questions & MCQs

Q1. What is AJAX Live Search?

A) Page reload search
B) Real-time search
C) Static search
D) Server-side search only

Answer: B

Q2. Which event is commonly used?

A) onclick
B) onchange
C) onkeyup
D) onsubmit

Answer: C

Q3. Which operator is used in SQL search?

A) IN
B) BETWEEN
C) LIKE
D) EXISTS

Answer: C

Q4. Best way to prevent SQL injection?

A) mysqli_query
B) Prepared statements
C) echo
D) htmlspecialchars

Answer: B

Q5. Live search improves?

A) Database size
B) UI/UX
C) Server load
D) Storage

Answer: B

Real-Life Use Cases

Google-like search
Admin user lookup
Product search
Email / username suggestions

Summary

AJAX Live Search = real-time search
Uses JavaScript + PHP + MySQL
LIKE operator for matching
No page reload
Prepared statements for security
Very important for interviews & projects

PHP AJAX Live Search Example