This is a snippet of a view query for employee sales.
CREATE OR REPLACE VIEW EMPLOYEE
AS
SELECT
customer.`Customer Name`,
customer.cid,
city_code.Dist_ID,
terretory.Executive,
terretory.Manager1,
terretory.Manager2,
district.Dist_Name,
SUM(item.Sales_Amount) As Sales_Amount
FROM customer
INNER JOIN city_code
ON city_code.City_id=customer.City_id
INNER JOIN district
ON district.Dist_Id=city_code.Dist_ID
INNER JOIN terretory
ON terretory.District_ID=district.Dist_Name
INNER JOIN sales_invoice
ON sales_invoice.CID=customer.cid
INNER JOIN sales_item
ON sales_item.Invoice_Number=sales_invoice.Invoice_Number
GROUP BY customer.`Customer Name`
The select operation is taking 2-3 minutes. How can the execution time be reduced? There are over 100,000 rows in the tables.