It looks like you’ve provided an image with an ER diagram and some SQL-related tasks. I’ll help you write SQL queries based on the provided diagram.
1. Retrieve all records from the DEMO_CUSTOMERS table:
SELECT * FROM DEMO_CUSTOMERS;2. Retrieve the first name, last name, and email of all customers:
SELECT CUST_FIRST_NAME, CUST_LAST_NAME, CUST_EMAIL FROM DEMO_CUSTOMERS;3. Retrieve all distinct states from the DEMO_CUSTOMERS table:
SELECT DISTINCT CUST_STATE FROM DEMO_CUSTOMERS;4. Retrieve the order ID, customer ID, and order total for all orders sorted by order total in descending order:
SELECT ORDER_ID, CUSTOMER_ID, ORDER_TOTAL
FROM DEMO_ORDERS
ORDER BY ORDER_TOTAL DESC;5. Find the total number of orders placed by each customer:
SELECT CUSTOMER_ID, COUNT(*) AS TOTAL_ORDERS
FROM DEMO_ORDERS
GROUP BY CUSTOMER_ID;6. Calculate the average order total for each customer:
SELECT CUSTOMER_ID, AVG(ORDER_TOTAL) AS AVERAGE_ORDER_TOTAL
FROM DEMO_ORDERS
GROUP BY CUSTOMER_ID;7. Retrieve all product names and their total quantities sold:
SELECT P.PRODUCT_NAME, SUM(OI.QUANTITY) AS TOTAL_QUANTITY_SOLD
FROM DEMO_PRODUCT_INFO P
JOIN DEMO_ORDER_ITEMS OI ON P.PRODUCT_ID = OI.PRODUCT_ID
GROUP BY P.PRODUCT_NAME;8. Find the highest order total in the DEMO_ORDERS table:
SELECT MAX(ORDER_TOTAL) AS HIGHEST_ORDER_TOTAL
FROM DEMO_ORDERS;9. Retrieve the name and price of all products that cost more than $50:
SELECT PRODUCT_NAME, LIST_PRICE
FROM DEMO_PRODUCT_INFO
WHERE LIST_PRICE > 50;10. Find the total sales amount for each product (unit price multiplied by quantity):
SELECT P.PRODUCT_NAME, SUM(OI.UNIT_PRICE * OI.QUANTITY) AS TOTAL_SALES_AMOUNT
FROM DEMO_PRODUCT_INFO P
JOIN DEMO_ORDER_ITEMS OI ON P.PRODUCT_ID = OI.PRODUCT_ID
GROUP BY P.PRODUCT_NAME;11. Retrieve the user name and the total number of orders processed by each user:
SELECT U.USER_NAME, COUNT(O.ORDER_ID) AS TOTAL_ORDERS_PROCESSED
FROM DEMO_USER U
JOIN DEMO_ORDERS O ON U.USER_ID = O.USER_ID
GROUP BY U.USER_NAME;12. Create a backup table CUSTOMER_BACKUP containing all records from the DEMO_CUSTOMERS table:
CREATE TABLE CUSTOMER_BACKUP AS
SELECT * FROM DEMO_CUSTOMERS;13. Insert data from the DEMO_CUSTOMERS table into the CUSTOMER_BACKUP table:
INSERT INTO CUSTOMER_BACKUP
SELECT * FROM DEMO_CUSTOMERS;14. Retrieve the total number of unique customers from the DEMO_ORDERS table:
SELECT COUNT(DISTINCT CUSTOMER_ID) AS TOTAL_UNIQUE_CUSTOMERS
FROM DEMO_ORDERS;15. Retrieve all orders placed in the year 2023:
SELECT * FROM DEMO_ORDERS
WHERE EXTRACT(YEAR FROM ORDER_TIMESTAMP) = 2023;Let me know if you need any more assistance!