Introduction:

This blog takes you on a journey through multiple methods to achieve the String to JSON conversion in MySQL, complete with code snippets and detailed explanations. By the end, you'll have a better understanding of various techniques to convert strings to JSON in MySQL.

Method 1: Utilizing JSON Functions

Starting from MySQL 5.7, JSON data type and accompanying functions were introduced, simplifying JSON manipulation. Follow these steps to convert a string to JSON:

• Set up a sample table:

CREATE TABLE json_conversion_demo (
    id INT AUTO_INCREMENT PRIMARY KEY,
    json_string VARCHAR(255)
);

• Insert example data:

INSERT INTO json_conversion_demo (json_string) VALUES ('{"key": "value"}');

• Convert string to JSON:

SELECT JSON_PARSE(json_string) AS json_data FROM json_conversion_demo;

Output:

+-----------------------+
| json_data             |
+-----------------------+
| {"key": "value"}      |
+-----------------------+

Method 2: Concatenation and JSON_PARSE

For MySQL versions predating 5.7, a combination of CONCAT and JSON_PARSE can be used:

• Set up the table and insert data (same as Method 1).
• Convert string to JSON:

SELECT JSON_PARSE(CONCAT('{"key": "', json_string, '"')) AS json_data FROM json_conversion_demo;

Output:

+-----------------------+
| json_data             |
+-----------------------+
| {"key": "value"}      |
+-----------------------+

Method 3: CAST and JSON_PARSE

CAST function combined with JSON_PARSE can also convert a string to JSON:

• Set up the table and insert data (same as Method 1).

• Convert string to JSON:

SELECT JSON_PARSE(CAST(CONCAT('{"key": "', json_string, '"') AS JSON)) AS json_data FROM json_conversion_demo;

Output:

+-----------------------+
| json_data             |
+-----------------------+
| {"key": "value"}      |
+-----------------------+

Conclusion:

In this blog, we've explored the various methods for converting strings to JSON within MySQL. We started with the convenient JSON functions introduced in MySQL 5.7, which provide an elegant solution. For those using older versions, we explored alternative methods using CONCAT, CAST.