Postgres 15

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CREATE TABLE mytable (
  id int, 
  favorites jsonb
);

insert into mytable values
(1,	'{ "shapes": ["Triangle", "Square", "Rectangle", "Circle"] }'),
(2,	'{ "shapes": ["Rectangle", "Triangle", "Circle"] }');

CREATE TABLE

INSERT 0 2

select *
from mytable;

id
favorites

1
{"shapes": ["Triangle", "Square", "Rectangle", "Circle"]}

2
{"shapes": ["Rectangle", "Triangle", "Circle"]}

SELECT 2

update mytable
set favorites = 
    jsonb_set(favorites, '{shapes}', (favorites->'shapes') - 'Square');

UPDATE 2

select *
from mytable;

id
favorites

1
{"shapes": ["Triangle", "Rectangle", "Circle"]}

2
{"shapes": ["Rectangle", "Triangle", "Circle"]}

SELECT 2

id	favorites
1	{"shapes": ["Triangle", "Square", "Rectangle", "Circle"]}
2	{"shapes": ["Rectangle", "Triangle", "Circle"]}

id	favorites
1	{"shapes": ["Triangle", "Rectangle", "Circle"]}
2	{"shapes": ["Rectangle", "Triangle", "Circle"]}