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 table_28672269_1 (date_of_commissioning VARCHAR, unit_number VARCHAR)

### Question ###
What are Unit 2's dates of commissioning?

### Accurate SQL ###

SELECT COUNT(date_of_commissioning) FROM table_28672269_1 WHERE unit_number = 2