Postgres 16

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CREATE TABLE certificate (
  criterias text[]
);

INSERT INTO certificate VALUES
(ARRAY['{"url":"https://criteria.com", "description":"My Criteria"}', '{"url":"https://criteria2.com", "description":"Other Criteria"}'])
RETURNING *;

CREATE TABLE

criterias

{"{"url":"https://criteria.com", "description":"My Criteria"}","{"url":"https://criteria2.com", "description":"Other Criteria"}"}

INSERT 0 1

-- show
SELECT *
FROM   certificate c
CROSS  JOIN LATERAL (
   SELECT jsonb_agg(elem::jsonb) AS criterias_js
   FROM    unnest(c.criterias) elem
   ) sub;

criterias
criterias_js

{"{"url":"https://criteria.com", "description":"My Criteria"}","{"url":"https://criteria2.com", "description":"Other Criteria"}"}
[{"url": "https://criteria.com", "description": "My Criteria"}, {"url": "https://criteria2.com", "description": "Other Criteria"}]

SELECT 1

-- temp func for ALTER TABLE
CREATE OR REPLACE FUNCTION pg_temp.arr2jsb(text[])
  RETURNS jsonb
  LANGUAGE SQL IMMUTABLE STRICT PARALLEL safe
RETURN (
   SELECT jsonb_agg(elem::JSONB)
   FROM   unnest($1) elem
   );

CREATE FUNCTION

-- show func
SELECT *, pg_temp.arr2jsb(c.criterias)
FROM   certificate c;

criterias
arr2jsb

{"{"url":"https://criteria.com", "description":"My Criteria"}","{"url":"https://criteria2.com", "description":"Other Criteria"}"}
[{"url": "https://criteria.com", "description": "My Criteria"}, {"url": "https://criteria2.com", "description": "Other Criteria"}]

SELECT 1

-- ALTER TABLE                 
ALTER TABLE certificate
ALTER COLUMN criterias TYPE jsonb USING pg_temp.arr2jsb(criterias);

ALTER TABLE

TABLE certificate;

criterias

[{"url": "https://criteria.com", "description": "My Criteria"}, {"url": "https://criteria2.com", "description": "Other Criteria"}]

SELECT 1