When do all the researcher role staff start to work, and when do they stop working?
CREATE TABLE Project_Staff (date_from VARCHAR, date_to VARCHAR, role_code VARCHAR)
SELECT date_from, date_to FROM Project_Staff WHERE role_code = 'researcher'
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE Project_Staff (date_from VARCHAR, date_to VARCHAR, role_code VARCHAR) Question: When do all the researcher role staff start to work, and when do they stop working? [/INST] SELECT date_from, date_to FROM Project_Staff WHERE role_code = 'researcher' </s>