MySQL, Select records based on values in JSON array

Davina Leong picture Davina Leong · Aug 16, 2018 · Viewed 9.4k times · Source

I'm still pretty new to handling JSON fields in MySQL. All the solutions I've come across deal with objects that have key/values; unable to find one that handles JSON arrays.

Anyways, what I want to do is to be able to select all rows where the interestIds contain 2 in them. How do I do that? Thanks.

Users table

+----+-------------+
| id | interestIds |
+----+-------------+
|  1 | [1, 2]      |
|  2 | [3, 2]      |
|  3 | [2, 4]      |
+----+-------------+

Sample test query:

SET @userId = 2;
SELECT * FROM Users
WHERE @userId IN JSON_CONTAINS(@user, interestIds, '$[1]');

I am confused as how to use the JSON_* functions; not sure what to put for the 3rd parameter...

Answer

Sebastian Brosch picture Sebastian Brosch · Aug 16, 2018

You can use the following solution, using JSON_CONTAINS:

SELECT * 
FROM Users
WHERE JSON_CONTAINS(interestIds, '2') = 1;

The third (optional) paramater path gives you the posibility to use this function only on a specific part of your JSON value. So the following example checks if 2 is the second value of the array:

SELECT *
FROM test
WHERE JSON_CONTAINS(interestIds, '2', '$[1]') = 1;

demo on dbfiddle.uk