Postgres 12

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CREATE TABLE movies (
    contributors    JSONB
);

CREATE TABLE

INSERT INTO movies (contributors) VALUES('[
  {"last_name": "Robbins", "first_name": "Tim", "age": 61},
  {"last_name": "Freeman", "first_name": "Morgan", "age": 83}
]');

INSERT 0 1

ALTER TABLE movies ADD COLUMN search TSVECTOR
    GENERATED ALWAYS AS (TO_TSVECTOR('simple',
        jsonb_path_query_array(contributors, '$[*].last_name') /* ✅ */
    )) STORED;

ALTER TABLE

SELECT search FROM movies; /* Desired output: 'freeman':3 'robbin':1 */

search

'freeman':3 'robbins':1

SELECT 1