This code is all you will need to build a simple SEARCH function using MySQL & PHP.
<form method="post">
<input type="text" name="inp_search" id="inp_search" autocomplete="off">
<button type="submit" name="btn_search">Search</button>
</form>
<table>
<tr>
<th>#</th>
<th>First name</th>
<th>Last name</th>
<th>Age</th>
</tr>
<?php
$conn = mysqli_connect('localhost', 'root', '', 'crud-app');
if (!$conn) {
die ("No connection" . mysqli_connect_error($conn));
}
if (isset($_POST['btn_search'])) {
$search = $_POST['inp_search'];
$query = "SELECT * FROM `crud-app-tbl` WHERE id='$search' or
first_name LIKE '%$search%' or last_name LIKE '%$search%'";
$result = mysqli_query($conn, $query);
if (mysqli_num_rows($result) > 0) {
while ($row = mysqli_fetch_assoc($result)) {
echo '<tr>
<td><a href="#">' . $row['id'] . '</a></td>
<td>' . $row['first_name'] . '</td>
<td>' . $row['last_name'] . '</td>
<td>' . $row['age'] . '</td>
</tr>';
}
} else {
echo 'No data!';
}
} else {
echo 'Start your SEARCH here!';
}
?>
</table>