How do I handle NULL values

Handling NULL values in MySQL is essential for ensuring data integrity and accurate query results. NULL values represent missing or unknown data, and different SQL functions can be utilized to manage them effectively. Below is a simple example of how to work with NULL values in MySQL.

<?php // Database connection $conn = new mysqli("localhost", "username", "password", "database"); // Check connection if ($conn->connect_error) { die("Connection failed: " . $conn->connect_error); } // Example of handling NULL values $sql = "SELECT id, name, age FROM users WHERE age IS NULL"; $result = $conn->query($sql); if ($result->num_rows > 0) { // Output data of each row while($row = $result->fetch_assoc()) { echo "id: " . $row["id"]. " - Name: " . $row["name"]. " - Age: " . $row["age"]. "<br>"; } } else { echo "0 results"; } $conn->close(); ?>

MySQL NULL values handling NULL SQL queries database management

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