Как создать индекс по столбцу JSON в Postgresql

Question

Структура моей таблицы, например

CREATE TABLE sp_custom.test_table
(
  application_id integer NOT NULL,
  service_id integer,
  initiated_data json,
  execution_data json,
  CONSTRAINT pk_appl_process_json PRIMARY KEY (application_id)
  );

и JSON структура

{
    "appl_info": {
        "department_id": 544,
        "department_name": "Excise Department of Kerala",
        "service_id": 11210004,
        "service_name": "TestDSCOptional",
        "appl_id": 7737,
        "appl_ref_no": "TESTDSCOPT/2019/00379",
        "no_of_attachment": 0,
        "submission_mode_id": 112,
        "submission_mode": "online",
        "applied_by": "citizenke",
        "submission_location": "Office of Deputy Excise Commissioner( DISTRICT - ALAPPUZHA )",
        "submission_date": "21-10-2019 10:50:46",
        "payment_mode": null,
        "reference_no": null,
        "payment_date": null,
        "amount": null,
        "registration_id": "",
        "base_service_id": 1121,
        "version_no": 4,
        "sub_version": 4,
        "due_date": null
    },
    "application_form_attributes": {
        "65119": "/opt/preprod/folders/ApplicantImage/32/11210004/17636/17636_3295_65119.jpg",
        "65176": "asdasd",
        "65121": "603~NICOBARS",
        "65120": "35~ANDAMAN AND NICOBAR ISLANDS",
        "65122": "5916~Car Nicobar"
    },
    "enclosure_data": null
}