php Mysql
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PHP & MySQL – Handling NULL Example
You can use the if…else condition to prepare a query based on the NULL value.
The following example takes the tutorial_count from outside and then compares it with the value available in the table.
Example
Copy and paste the following example as mysql_example.php −
<html>
<head>
<title>Handling NULL</title>
</head>
<body>
<?php
$dbhost = ''localhost
$dbuser = ''root
$dbpass = ''root@123
$dbname = ''TUTORIALS
$mysqli = new mysqli($dbhost, $dbuser, $dbpass, $dbname);
$tutorial_count = null;
if($mysqli->connect_errno ) {
printf("Connect failed: %s<br />", $mysqli->connect_error);
exit();
}
printf(''Connected successfully.<br />'');
if( isset($tutorial_count )) {
$sql = ''SELECT tutorial_author, tutorial_count
FROM tcount_tbl
WHERE tutorial_count = '' + $tutorial_count;
} else {
$sql = ''SELECT tutorial_author, tutorial_count
FROM tcount_tbl
WHERE tutorial_count IS NULL
}
$result = $mysqli->query($sql);
if ($result->num_rows > 0) {
while($row = $result->fetch_assoc()) {
printf("Author: %s, Count: %d <br />",
$row["tutorial_author"],
$row["tutorial_count"]);
}
} else {
printf(''No record found.<br />'');
}
$mysqli->close();
?>
</body>
</html>
Output
Access the mysql_example.php deployed on apache web server and verify the output.
Connected successfully. No record found.
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