Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE employees (email VARCHAR, department_id VARCHAR, commission_pct VARCHAR, salary VARCHAR)

### Question ###
display the emails of the employees who have no commission percentage and salary within the range 7000 to 12000 and works in that department which number is 50.

### Accurate SQL ###

SELECT email FROM employees WHERE commission_pct = "null" AND salary BETWEEN 7000 AND 12000 AND department_id = 50