Why Does My MySQL JSON Output Show NULL Values for Description Fields?

MySQL JSON Output: Hidden Null Values

When using json_encode() to convert database data to JSON, unexpected NULL values can arise, hindering data integrity. This article explores why description returns NULL in the provided code snippet and offers a solution to resolve the issue.

The code snippet retrieves records from a MySQL database table named staff and attempts to encode the results into JSON format. However, the description field returns NULL in the JSON output, despite containing data in the database.

The root cause of this issue lies in the character encoding. MySQL may not be retrieving data in UTF-8 encoding, leading to encoding inconsistencies and NULL values for non-UTF-8 characters.

To rectify the problem, add mysql_query('SET CHARACTER SET utf8') before the SELECT query. This sets the character set for the database connection, ensuring that data is retrieved in UTF-8 encoding.

After implementing this modification, json_encode() will correctly handle UTF-8 characters in the description field, and the JSON output will accurately represent the database data.

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