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 Project_Staff ( date_from VARCHAR )

### Question ###
When did the first staff for the projects started working?

### Accurate SQL ###

SELECT date_from FROM Project_Staff ORDER BY date_from LIMIT 1