cross engine join query select on decimal bad precision/scale

CREATE TABLE employees (

  `id` INT NOT NULL,

  `name` VARCHAR(255) NOT NULL

) ENGINE=Columnstore;

CREATE TABLE roles (

  `employee_id` INT NOT NULL,

  `role` VARCHAR(255) NOT NULL,

  `salary` DECIMAL(12,8) NOT NULL DEFAULT '9.9'

) ENGINE=InnoDB;

INSERT INTO employees (`id`, `name`) VALUES (1, 'John'), (2, 'Mary');

INSERT INTO roles (`employee_id`, `role`, `salary`) VALUES (1, 'Programmer', 3.33), (2, 'DBA', 4.57);

-- Correct result. Show 2 rows with values 3.33 and 4.57

SELECT * FROM roles;

-- Incorrect result. Both salaries are 9.90000000 (which is the default value for the column)

SELECT name, salary FROM employees JOIN roles on employees.id = roles.employee_id;