IS NULL
MySQL IS NULL operator tests whether a value is NULL. If satisfied, then returns 1 otherwise returns 0.
Syntax:
IS NULL
MySQL Version: 5.6
Example : MySQL IS NULL
In the following MySQL statement, it is checked whether 2, 0 and NULL are NULL, using IS NULL operator.
Code:
SELECT 2 IS NULL, 0 IS NULL, NULL IS NULL;
Sample Output:
mysql> SELECT 2 IS NULL, 0 IS NULL, NULL IS NULL; +-----------+-----------+--------------+ | 2 IS NULL | 0 IS NULL | NULL IS NULL | +-----------+-----------+--------------+ | 0 | 0 | 1 | +-----------+-----------+--------------+ 1 row in set (0.00 sec)
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<h2>Testing whether a value is NULL using MySQL. It returned 1 if the value id NULL else returns 0:</h2>
<table class='table table-bordered'>
<tr>
<th>2 IS NULL</th><th>0 IS NULL</th><th>NULL IS NULL</th>
</tr>
<?php
$hostname="your_hostname";
$username="your_username";
$password="your_password";
$db = "your_dbname";
$dbh = new PDO("mysql:host=$hostname;dbname=$db", $username, $password);
foreach($dbh->query('SELECT 2 IS NULL, 0 IS NULL, NULL IS NULL') as $row) {
echo "<tr>";
echo "<td>" . $row['2 IS NULL'] . "</td>";
echo "<td>" . $row['0 IS NULL'] . "</td>";
echo "<td>" . $row['NULL IS NULL'] . "</td>";
echo "</tr>";
}
?>
</tbody></table>
</div>
</div>
</div>
</body>
</html>
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