##Instruction:
Database: cre_Drama_Workshop_Groups
Total Tables: 18
Total Columns: 99

Table Schemas:

cre_Drama_Workshop_Groups contains tables such as Ref_Payment_Methods, Ref_Service_Types, Addresses, Products, Marketing_Regions, Clients, Drama_Workshop_Groups, Performers, Customers, Stores, Bookings, Performers_in_Bookings, Customer_Orders, Order_Items, Invoices, Services, Bookings_Services, Invoice_Items.
Table Ref_Payment_Methods has columns such as payment_method_code, payment_method_description.
payment_method_code is the primary key.
Table Ref_Service_Types has columns such as Service_Type_Code, Parent_Service_Type_Code, Service_Type_Description.
Service_Type_Code is the primary key.
Table Addresses has columns such as Address_ID, Line_1, Line_2, City_Town, State_County, Other_Details.
Address_ID is the primary key.
Table Products has columns such as Product_ID, Product_Name, Product_Price, Product_Description, Other_Product_Service_Details.
Product_ID is the primary key.
Table Marketing_Regions has columns such as Marketing_Region_Code, Marketing_Region_Name, Marketing_Region_Descriptrion, Other_Details.
Marketing_Region_Code is the primary key.
Table Clients has columns such as Client_ID, Address_ID, Customer_Email_Address, Customer_Name, Customer_Phone, Other_Details.
Client_ID is the primary key.
Table Drama_Workshop_Groups has columns such as Workshop_Group_ID, Address_ID, Currency_Code, Marketing_Region_Code, Store_Name, Store_Phone, Store_Email_Address, Other_Details.
Workshop_Group_ID is the primary key.
Table Performers has columns such as Performer_ID, Address_ID, Customer_Name, Customer_Phone, Customer_Email_Address, Other_Details.
Performer_ID is the primary key.
Table Customers has columns such as Customer_ID, Address_ID, Customer_Name, Customer_Phone, Customer_Email_Address, Other_Details.
Customer_ID is the primary key.
Table Stores has columns such as Store_ID, Address_ID, Marketing_Region_Code, Store_Name, Store_Phone, Store_Email_Address, Other_Details.
Store_ID is the primary key.
Table Bookings has columns such as Booking_ID, Customer_ID, Workshop_Group_ID, Status_Code, Store_ID, Order_Date, Planned_Delivery_Date, Actual_Delivery_Date, Other_Order_Details.
Booking_ID is the primary key.
Table Performers_in_Bookings has columns such as Order_ID, Performer_ID.
Order_ID is the primary key.
Table Customer_Orders has columns such as Order_ID, Customer_ID, Store_ID, Order_Date, Planned_Delivery_Date, Actual_Delivery_Date, Other_Order_Details.
Order_ID is the primary key.
Table Order_Items has columns such as Order_Item_ID, Order_ID, Product_ID, Order_Quantity, Other_Item_Details.
Order_Item_ID is the primary key.
Table Invoices has columns such as Invoice_ID, Order_ID, payment_method_code, Product_ID, Order_Quantity, Other_Item_Details, Order_Item_ID.
Invoice_ID is the primary key.
Table Services has columns such as Service_ID, Service_Type_Code, Workshop_Group_ID, Product_Description, Product_Name, Product_Price, Other_Product_Service_Details.
Service_ID is the primary key.
Table Bookings_Services has columns such as Order_ID, Product_ID.
Order_ID is the primary key.
Table Invoice_Items has columns such as Invoice_Item_ID, Invoice_ID, Order_ID, Order_Item_ID, Product_ID, Order_Quantity, Other_Item_Details.
Invoice_Item_ID is the primary key.
The Address_ID of Clients is the foreign key of Address_ID of Addresses.
The Address_ID of Drama_Workshop_Groups is the foreign key of Address_ID of Addresses.
The Address_ID of Performers is the foreign key of Address_ID of Addresses.
The Address_ID of Customers is the foreign key of Address_ID of Addresses.
The Marketing_Region_Code of Stores is the foreign key of Marketing_Region_Code of Marketing_Regions.
The Address_ID of Stores is the foreign key of Address_ID of Addresses.
The Workshop_Group_ID of Bookings is the foreign key of Workshop_Group_ID of Drama_Workshop_Groups.
The Customer_ID of Bookings is the foreign key of Client_ID of Clients.
The Order_ID of Performers_in_Bookings is the foreign key of Booking_ID of Bookings.
The Performer_ID of Performers_in_Bookings is the foreign key of Performer_ID of Performers.
The Store_ID of Customer_Orders is the foreign key of Store_ID of Stores.
The Customer_ID of Customer_Orders is the foreign key of Customer_ID of Customers.
The Product_ID of Order_Items is the foreign key of Product_ID of Products.
The Order_ID of Order_Items is the foreign key of Order_ID of Customer_Orders.
The payment_method_code of Invoices is the foreign key of payment_method_code of Ref_Payment_Methods.
The Order_ID of Invoices is the foreign key of Booking_ID of Bookings.
The Order_ID of Invoices is the foreign key of Order_ID of Customer_Orders.
The Service_Type_Code of Services is the foreign key of Service_Type_Code of Ref_Service_Types.
The Workshop_Group_ID of Services is the foreign key of Workshop_Group_ID of Drama_Workshop_Groups.
The Product_ID of Bookings_Services is the foreign key of Service_ID of Services.
The Order_ID of Bookings_Services is the foreign key of Booking_ID of Bookings.
The Order_ID of Invoice_Items is the foreign key of Order_ID of Bookings_Services.
The Product_ID of Invoice_Items is the foreign key of Product_ID of Bookings_Services.
The Invoice_ID of Invoice_Items is the foreign key of Invoice_ID of Invoices.
The Order_Item_ID of Invoice_Items is the foreign key of Order_Item_ID of Order_Items.

##Role Access Policy (Column-Level):
Role: ClientRelations
Accessible Columns: Clients: Client_ID, Customer_Name, Customer_Phone, Customer_Email_Address, Other_Details; Bookings: Booking_ID, Customer_ID, Workshop_Group_ID, Status_Code, Order_Date, Planned_Delivery_Date, Actual_Delivery_Date, Other_Order_Details; Drama_Workshop_Groups: Workshop_Group_ID, Store_Name, Store_Phone, Store_Email_Address; Services: Service_ID, Service_Type_Code, Product_Name, Product_Description, Product_Price

Based on the above schema and your role's column-level access policy, generate a SQL query to answer the question. If your role does not have access to the required columns, respond with: "Sorry, I cannot answer."


Question: What are the names of the clients who do not have any booking?
Answer: SELECT Customer_Name FROM Clients EXCEPT SELECT T2.Customer_Name FROM Bookings AS T1 JOIN Clients AS T2 ON T1.Customer_ID  =  T2.Client_ID
Permission: allowed (All required columns are permitted)
Gold SQL: SELECT Customer_Name FROM Clients EXCEPT SELECT T2.Customer_Name FROM Bookings AS T1 JOIN Clients AS T2 ON T1.Customer_ID  =  T2.Client_ID