You can unnest the array withjsonb_array_elements(), modify filtered elements and finally aggregate the result into a json array usingjsonb_agg(). Use simply concatenation operator to replace an inner json object.

Example (jsonb_pretty() not necessary, used for a nice output):

with my_table(data) as (values(    '[        {"schedule_id":1,"datetime":"2017-05-12 00:00:00","status":"available"},        {"schedule_id":2,"datetime":"2017-05-12 02:00:00","status":"available"}    ]'::jsonb))select    jsonb_pretty(jsonb_agg(        case value->>'schedule_id'        when '2' then value || '{"status":"booked"}'        else value        end    ))from my_table,jsonb_array_elements(data);                jsonb_pretty                -------------------------------------------- [                                         +     {                                     +         "status": "available",            +         "datetime": "2017-05-12 00:00:00",+         "schedule_id": 1                  +     },                                    +     {                                     +         "status": "booked",               +         "datetime": "2017-05-12 02:00:00",+         "schedule_id": 2                  +     }                                     + ](1 row)

The easiest way to use this for updating a table is to enclose the query in a custom function, e.g.:

create or replace function change_schedule_status(schedule jsonb, id int, status text)returns jsonb language sql as $$    select        jsonb_agg(            case value->>'schedule_id'            when id::text then value || jsonb_build_object('status', status)            else value            end        )    from jsonb_array_elements(schedule);$$;update searchset schedule = change_schedule_status(schedule, 2, 'booked')where id = 1  -- probably the table has a primary key?returning *;

• arrays
• json
• postgresql
• jsonb
• postgresql-9.6