How can PHP be used to check if an entry in a MySQL database already exists while ignoring case sensitivity?

When checking if an entry in a MySQL database already exists while ignoring case sensitivity, you can use the `LOWER()` function in your SQL query to convert both the database column value and the input value to lowercase before comparing them. This ensures that the comparison is case-insensitive. 

<?php
// Database connection
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "database";

$conn = new mysqli($servername, $username, $password, $dbname);

// Check connection
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}

// Input value
$input_value = "Example";

// Query to check if entry exists while ignoring case sensitivity
$sql = "SELECT * FROM table_name WHERE LOWER(column_name) = LOWER('$input_value')";

$result = $conn->query($sql);

if ($result->num_rows > 0) {
    echo "Entry already exists!";
} else {
    echo "Entry does not exist.";
}

$conn->close();
?>

Keywords

PHP MySQL case-insensitive database entry check

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