


Why Does My JSON Encoding Return NULL for the Description Field?
JSON Encoding Returns Null for Description Field
In this scenario, the "description" field returns NULL in JSON-encoded output. Initially, the code extracts data from a database table using a MySQL query and stores it in an array. Subsequently, the content of the array is JSON-encoded.
Examining the database table reveals a schema that includes a "description" field. However, the output JSON does not include any data for this field.
The issue is most likely related to the character encoding:
Character Encoding Issue
The database character set and the PHP character encoding may differ. It is advisable to set the database connection and query to use UTF-8 encoding explicitly using the following code before the SELECT query:
Impact of Character Encoding
Character encoding defines how characters are represented in a text file or database. Mismatches between encodings can lead to incorrect data retrieval or display.
By setting the character set to UTF-8 in both the database connection and query, you ensure that the data retrieved matches the character set expected by the PHP script for encoding in JSON. This should resolve the NULL issue for the "description" field.
The above is the detailed content of Why Does My JSON Encoding Return NULL for the Description Field?. For more information, please follow other related articles on the PHP Chinese website!

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