Querying data within JSON array data field
json_array_elements(...) returns a set, and so does the result of applying ->> and = to the set. Observe:
regress=> select json_array_elements('[{"name": "foo", "account_id": "123"}, {"name": "bar", "account_id": "321"}]') ->> 'account_id' = '123'; ?column? ---------- t f(2 rows)You'd expect to just be able to write '123' = ANY (...) but that's not supported without an array input, unfortunately. Surprisingly, neither is '123' IN (...), something I think we're going to have to fix.
So, I'd use LATERAL. Here's one way, which will return a company ID multiple times if it has multiple matches:
CREATE TABLE company AS SELECT 1 AS id, '[{"name": "foo", "account_id": "123"}, {"name": "bar", "account_id": "321"}]'::json AS accounts;SELECT id FROM company c,LATERAL json_array_elements(c.accounts) acc WHERE acc ->> 'account_id' = '123';