PostgreSQL: Remove Multiple Keys From JSONB

jsonb_remove_keys.sql

CREATE OR REPLACE FUNCTION jsonb_remove_keys(
	jdata JSONB,
	keys TEXT[]
)
RETURNS JSONB AS $$
DECLARE
	result JSONB;
	len INT;
	target TEXT;
BEGIN
	len = array_length(keys, 1);
	result = jdata;
	FOR i IN 1..len LOOP
		target = keys[i];
		IF (jdata ? target) THEN
			result = (result - target);
		END IF;
	END LOOP;
	RETURN result;
END;
$$ LANGUAGE plpgsql;

Usage:

SELECT
  jsonb_remove_keys(
    '{"cityname": "haha", "id": 123, "name": {"foo": 222}}'::jsonb,
    ARRAY['name', 'cityname'])