CREATE TABLE invoice (

  id INTEGER PRIMARY KEY AUTO_INCREMENT NOT NULL,

  amount DOUBLE DEFAULT NULL,

  name VARCHAR(100) DEFAULT NULL

);

INSERT INTO invoice (amount, name) 

VALUES (4.0, 'Michael'), (15.0, 'Bara'), (4.0, 'Michael'), (6.0, 'John');

SELECT sum(amount), name

from invoice

group by name

having sum(amount) > 6;

SELECT sum(amount), name

from invoice

group by name

having (select name = 'John'); -- refer parent data in subquery - ok!

SELECT sum(amount), name

from invoice

group by name

having (select sum(amount) > 6); -- refer parent aggregate data in subquery - ok!

SELECT sum(amount), name

from invoice

group by name

having (select sum(amount) > 6 from (select 1) t); -- still ok!

SELECT sum(amount), name

from invoice

group by name

having (select v > 6 from (select sum(amount) v) t); -- the same, only the `sum()` expr

                                                    -- is moved inside the subsubquery

SELECT sum(amount), name

from invoice

group by name

having (select v = 'John' from (select name v) t); -- even simple column reference

                                                  -- is broken