JSON_CONTAINS in HAVING clause adds extra closing brace to JSON_OBJECTAGG

I have a table with data we've collected from various sources. It's got the item name, the source and the source's value. The table looks like the following: | id | name | source | value | | -- | ---- | ------ | ----- | | 1 | abc | web | 1 | | 2 | abc | print | 2 | | 3 | xyz | print | 8 | | 4 | xyz | web | 9 | Using the JSON_OBJECTAGG() function, I can group the sources together based on the name:

SELECT name, JSON_OBJECTAGG(source, value) AS data
FROM testStuff
GROUP BY name

This correctly gives: | name | data | | ---- | --------------------- | | abc | {"web":1, "print": 2} | | xyz | {"print":8, "web": 9} | Now, I want to run that query, but with a filter on the price/source, so I ran the following query:

SELECT name, JSON_OBJECTAGG(source, value) AS data
FROM testStuff
GROUP BY name
HAVING JSON_CONTAINS(data, 2, '$.print')

This *seems* to work, but there's a slight issue: | name | data | | ---- | ---------------------- | | abc | {"web":1, "print": 2}} | Why is there suddenly an extra } at the end of the JSON data? The HAVING clause is correctly filtering the rows, but why does it modify the result data? Online demo: https://sqlfiddle.com/mariadb/online-compiler?id=ccf1041c-3ada-4fc9-bd77-2b0fe1428392 I'm not sure what version of MariaDB that site uses, but testing this on my local computer using MariaDB 10.11.9 gives the same results. **EDIT**: It seems I can fix this by using:

SELECT name, JSON_OBJECTAGG(source, value) AS data
FROM testStuff
GROUP BY name
HAVING JSON_CONTAINS(JSON_OBJECTAGG(source, value), 2, '$.print')

I just was trying to avoid writing the JSON_OBJECTAGG() multiple times. Also, while this fixes the issue, I still am curious as to why this was an issue in the first place. **EDIT 2**: Another "fix" is to replace JSON_OBJECTAGG() with GROUP_CONCAT(). The following returns the correct data:

SELECT name,
    REPLACE(GROUP_CONCAT(JSON_OBJECT(source, value)), '},{', ',') AS data
FROM testStuff
GROUP BY name
HAVING JSON_CONTAINS(data, 2, '$.print')