How can the normalization of relational databases and the use of JOINs in SQL benefit the handling of hierarchical data in PHP applications?

Normalizing relational databases and using JOINs in SQL can benefit the handling of hierarchical data in PHP applications by reducing data redundancy, improving data integrity, and simplifying data retrieval through efficient queries. By breaking down data into separate tables and establishing relationships between them, we can easily retrieve hierarchical data using JOIN operations in SQL. 

<?php
// Connect to the database
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";

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

// Query to retrieve hierarchical data using JOIN
$sql = "SELECT employees.name, departments.department_name
        FROM employees
        INNER JOIN departments ON employees.department_id = departments.id";

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

// Output the hierarchical data
if ($result->num_rows > 0) {
    while($row = $result->fetch_assoc()) {
        echo "Employee: " . $row["name"]. " - Department: " . $row["department_name"]. "<br>";
    }
} else {
    echo "0 results";
}

$conn->close();
?>

Keywords

Normalization relational databases JOINs hierarchical data PHP applications

Related Questions