Below is how an entry looks like in the Cassandra:
id | address | age | family | name | siblings
-----------------------------------------------------------------
1 | {'city': 'c1', 'rue': 'r1'} | 23 | si | si | {'b', 'd'}
I want to select based on the city which is a child of JSON in the address column:
I am not sure if the following are the correct statements:
select address from Persons address.city='f';
select address.city from Persons ;
Unfortunately, that cannot be done in Cassandra (at least for now).
One possible option is to change your model to something like
id | city | rue | age | family | name | siblings
----+------+-----+-------------------------------
1 | c1 | r1 | 23 | si | si | {'b', 'd'}
then you will be able to execute query:
select json city, rue from addresses where city = 'c1';
to achieve "ready-to-use" json in result:
[json]
-----------------------------
{"city": "c1", "rue": "r1"}