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 settlements ( settlement_id number, claim_id number, effective_date time, settlement_amount number )
TABLE: CREATE TABLE services ( service_id number, service_name text )
TABLE: CREATE TABLE available_policies ( policy_id number, policy_type_code text, customer_phone text )
TABLE: CREATE TABLE customers ( customer_id number, customer_name text )
TABLE: CREATE TABLE claims ( claim_id number, fnol_id number, effective_date time )
TABLE: CREATE TABLE customers_policies ( customer_id number, policy_id number, date_opened time, date_closed time )
TABLE: CREATE TABLE first_notification_of_loss ( fnol_id number, customer_id number, policy_id number, service_id number )

### Question ###
Retrieve the open and close dates of all the policies associated with the customer whose name contains 'Diana

### Accurate SQL ###

SELECT t2.date_opened, t2.date_closed FROM customers AS t1 JOIN customers_policies AS t2 ON t1.customer_id = t2.customer_id WHERE t1.customer_name LIKE "%Diana%"