How to deal with JSON column while using GROUP BY

I’m using a query similar to the below one, address is JSON TYPE.

SELECT id, name, MAX(salary), age, adress FROM test group by id, name, age

​x
 
SELECT id, name, MAX(salary), age, adress FROM test group by id, name, age​

But getting below error:

SQL Error [42883]: ERROR: could not identify an equality operator for type json
  Position: 152

 
SQL Error [42883]: ERROR: could not identify an equality operator for type json  Position: 152​

I’m trying to get the data of a person who has the max salary for his age and I need to include adress filed which should be JSON

So, Is the there any way to achieve this or is this practically possible ?

Note:- postgres db

Answer

I’d go with DISTINCT ON() instead:

SELECT DISTINCT ON (age) id, name, salary, age, adress
FROM test
ORDER BY age, salary desc

 
SELECT DISTINCT ON (age) id, name, salary, age, adressFROM testORDER BY age, salary desc​

The DISTINCT ON (age) will give you one row for each age. The one with the highest salary, as the ORDER BY decides.