


Why does `json_encode()` return NULL for MySQL database fields, and how can I fix it?
JSON_ENCODE Returns NULL for Database Fields
While working with MySQL and PHP, you may encounter an issue where json_encode() returns NULL for fields in your database. Here's a specific example:
$result = mysql_query('SELECT * FROM `staff` ORDER BY `id` DESC LIMIT 2') or die(mysql_error()); $rows = array(); while($row = mysql_fetch_assoc($result)){ $rows[] = $row; } echo json_encode($rows);
Possible Cause:
After investigating your database schema and the echoed output, it's likely that you're retrieving data in a non-UTF8 encoding.
Solution:
To resolve this issue, add the following line before your SELECT query:
mysql_query('SET CHARACTER SET utf8');
This command ensures that your MySQL connection uses UTF-8 encoding, which is required for json_encode() to properly handle UTF-8 characters in your database fields.
Updated Code:
mysql_query('SET CHARACTER SET utf8'); $result = mysql_query('SELECT * FROM `staff` ORDER BY `id` DESC LIMIT 2') or die(mysql_error()); $rows = array(); while($row = mysql_fetch_assoc($result)){ $rows[] = $row; } echo json_encode($rows);
Expected Output:
Now, when you run the updated code, you should get the following output, where the "description" field contains non-NULL values:
[{"id":"4","name":"Noter 2","description":"Description of Noter 2","icon":"http:\/\/images.apple.com\/webapps\/productivity\/images\/noter2_20091223182720-thumb.jpg","date":"1262032317","company":"dBelement, LLC","companyurl":"http:\/\/dbelement.com\/","appurl":"http:\/\/noter2.dbelement.com"},{"id":"3","name":"Noter 2","description":"Description of Noter 2","icon":"http:\/\/images.apple.com\/webapps\/productivity\/images\/noter2_20091223182720-thumb.jpg","date":"1262032317","company":"dBelement, LLC","companyurl":"http:\/\/dbelement.com\/","appurl":"http:\/\/noter2.dbelement.com"}]
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