Remove json object from array of jsons in postgres - sql

Question

I have the following json in my column in posgres database.
Column items in table products
{
"name": "Super name",
"type": "Green",
"information": [
{
"name": "first",
"value": "high"
},
{
"name": "second",
"value": "medium"
}
],
}
I want to delete json object using jsonb
{
"name": "second",
"value": "medium"
}
I try this:
update products set items = jsonb_set(items, '{information}', (items->'information') - '{"name": "second", "value": "medium"}');
I tried different approaches but nothing work correctly.

Answer 1

The "minus" operator doesn't work on objects, only keys. And it doesn't work on arrays of objects either.
I would write a function that removes a single object from an array.
create function remove_element(p_input jsonb, p_to_remove jsonb)
returns jsonb
as
$$
select coalesce(jsonb_agg(t.item order by t.idx), '[]')
from jsonb_array_elements(p_input) with ordinality as t(item, idx)
where t.item <> p_to_remove;
$$
language sql
immutable;
Then you can use it like this:
update products
set items = jsonb_set(items, '{information}', remove_element(items -> 'information', '{"name": "second", "value": "medium"}'))
where ...
Online example