How to query deep jsonb in Postgres? - postgresql

Question

I have a jsonb column (called info) in Postgres which structure looks like this:
{ name: 'john', house_id: null, extra_attrs: [{ attr_id: 4, attr_value: 'a value' }, { attr_id: 5, attr_value: 'another value' }] }
It can have N extra_attrs but we know that each of them will have just two keys: the attr_id and the attr_value.
Now, what is the best way to query for info that has extra_attrs with a specific attr_id and attr_value. I have done it like this, and it works:
Given the following data structure to query for:
[{ attr_id: 4, values: ['a value', 'something else'] }, { attr_id: 5, values: ['another value'] }]
The following query works:
select * from people
where (info #> '{"extra_attrs": [{ "attr_id": 4, "attr_value": "a value" }]} OR info #> '{"extra_attrs": [{ "attr_id": 4, "attr_value": "something else" }]) AND info #> '{"extra_attrs": [{ "attr_id": 5, "attr_value": "another value" }]}
I am wondering if there is a better way to do so or this is fine.

Answer 1

One alternate method would involve json functions and transforming data to apply the filter on:
SELECT people.info
FROM people,
LATERAL (SELECT DISTINCT True is_valid
FROM jsonb_array_elements(info->'extra_attrs') y
WHERE (y->>'attr_id', y->>'attr_value') IN (
('4', 'a value'),
('4', 'something else'),
('5','another value')
)
) y
WHERE is_valid
I believe this method more convenient for dynamic filters since the id/value pairs are added in only 1 place.
A similar (and perhaps slightly faster) method would use WHERE EXISTS and compare json documents like below.
SELECT people.info
FROM people
WHERE EXISTS (SELECT TRUE
FROM jsonb_array_elements(info->'extra_attrs') attrs
WHERE attrs #> ANY(ARRAY[
JSONB '{ "attr_id": 4, "attr_value": "a value" }',
JSONB '{ "attr_id": 4, "attr_value": "something else" }',
JSONB '{ "attr_id": 5, "attr_value": "another value" }'
]
)
)