Postgres 11

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select version();

CREATE TABLE my_json (
    id serial,
    data jsonb
);

INSERT INTO my_json (data)
VALUES
    ('{"1":{"1":{"level":2,"nodeType":2,"id":2,"parentNode":1,"attribute_id":363698007,"attribute_text":"Finding site","concept_id":386108004,"description_text":"Heart tissue","hierarchy_id":0,"description_id":-1,"deeperCnt":0,"default":false},"level":1,"nodeType":1,"id":1,"parentNode":0,"concept_id":22253000,"description_id":37361011,"description_text":"Pain","hierarchy_id":404684003,"deeperCnt":1,"default":false},"2":{"1":{"attribute_id":"363698007","attribute_text":"Finding site (attribute)","value_id":"321667001","value_text":"Respiratory tract structure (body structure)","default":true},"level":1,"nodeType":1,"id":3,"parentNode":0,"concept_id":11833005,"description_id":20419011,"description_text":"Dry cough","hierarchy_id":404684003,"deeperCnt":1,"default":false},"level":0,"recAddedLevel":1,"recAddedId":3,"nodeType":0,"multiple":false,"currNodeId":3,"id":0,"lookForAttributes":false,"deeperCnt":2}'::jsonb),
    ('{"attribute_id":363698007,"id":23,"attribute_text":"Finding site #2"}'::jsonb),
    ('{"attribute_id":123,"concept_id":386108005,"id":42}'::jsonb)
;

version
PostgreSQL 11.9 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 8.3.1 20191121 (Red Hat 8.3.1-5), 64-bit

3 rows affected

id	id_from_json
2	23
1	0