Postgres 12

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CREATE TABLE visitor (name varchar(255), hobbies text[]);
CREATE TABLE hobbies(name varchar(255), id text);

INSERT INTO visitor (name, hobbies) VALUES ('sanghin', '{ida}');
INSERT INTO hobbies (name, id) VALUES ('sql', 'ida');

CREATE TABLE

CREATE TABLE

INSERT 0 1

INSERT 0 1

SELECT hobbies FROM visitor WHERE visitor.name = 'sanghin'

hobbies

{ida}

SELECT 1

SELECT name FROM hobbies WHERE id IN (SELECT unnest(hobbies) FROM visitor WHERE visitor.name = 'sanghin');

name

sql

SELECT 1