MariaDB 10.4

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select version();

version()

10.4.7-MariaDB-1:10.4.7+maria~buster

create table myjson(data json);
insert into myjson values ('{"foo": "bar"}');
insert into myjson values ('"bar"');
select * from myjson where json_extract(data, '$.foo') = json_extract('"bar"', '$');
select * from myjson where json_extract(data, '$.foo') = json_unquote(json_extract('"bar"', '$'));

data

{"foo": "bar"}

select * from myjson where json_unquote(json_extract(data, '$.foo')) = json_extract('"bar"', '$');
select * from myjson where json_unquote(json_extract(data, '$.foo')) = json_unquote(json_extract('"bar"', '$'));

data

{"foo": "bar"}

select * from myjson where json_extract(data, '$') = 'bar';

data

"bar"

select * from myjson where json_unquote(json_extract(data, '$')) = 'bar';

data

"bar"

select json_extract('"bar"', '$');

json_extract('"bar"', '$')

"bar"

select json_unquote(json_extract('"bar"', '$'));

json_unquote(json_extract('"bar"', '$'))

bar

select json_extract('{"foo": "bar"}', '$.foo');

json_extract('{"foo": "bar"}', '$.foo')

"bar"

select json_unquote(json_extract('{"foo": "bar"}', '$.foo'));

json_unquote(json_extract('{"foo": "bar"}', '$.foo'))

bar

select json_extract('{"foo": "bar"}', '$.foo') = json_extract('{"foo": "bar"}', '$.foo');

json_extract('{"foo": "bar"}', '$.foo') = json_extract('{"foo": "bar"}', '$.foo')

0

select json_unquote(json_extract('{"foo": "bar"}', '$.foo')) = json_unquote(json_extract('{"foo": "bar"}', '$.foo'));

json_unquote(json_extract('{"foo": "bar"}', '$.foo')) = json_unquote(json_extract('{"foo": "bar"}', '$.foo'))

1

select json_extract('{"foo": "bar"}', '$.foo') = json_unquote(json_extract('{"foo": "bar"}', '$.foo'));

json_extract('{"foo": "bar"}', '$.foo') = json_unquote(json_extract('{"foo": "bar"}', '$.foo'))

0

select json_unquote(json_extract('{"foo": "bar"}', '$.foo')) = json_extract('{"foo": "bar"}', '$.foo');

json_unquote(json_extract('{"foo": "bar"}', '$.foo')) = json_extract('{"foo": "bar"}', '$.foo')

0

select json_extract('{"foo": "bar"}', '$.foo') = json_unquote(json_extract('"bar"', '$'));

json_extract('{"foo": "bar"}', '$.foo') = json_unquote(json_extract('"bar"', '$'))

0

# If the above is false, then how come this yields a result?
select * from myjson where json_extract(data, '$.foo') = json_unquote(json_extract('"bar"', '$'));

data

{"foo": "bar"}