Merge branch 'master' of https://git.fullstacksyntra.be/bdelepeleer/How_to_code_summary_queries into master

README.md

@@ -73,24 +73,4 @@ Return these columns:
 
 This should return 2 rows.
 
-### Exercise 8
 
-Write a SELECT statement that answers this question: What are the last payment date and total amount due for each vendor with each terms id? Return these columns:
-
-- The terms_id column from the Invoices table The vendor_id column from the Invoices table
-- The last payment date for each combination of terms id and vendor id in the Invoices table - The sum of the balance due (invoice_total - payment_total - credit_total) for each combination of terms id and vendor id in the Invoices table
-
-Use the WITH ROLLUP operator to include rows that give a summary for each terms id as well as a row that gives the grand total. This should return 40 rows.
-
-Use the IF and GROUPING functions to replace the null values in the terms_id and vendor_id columns with literal values if they’re for summary rows.
-
-### Exercise 9
-
-Write a SELECT statement that uses aggregate window functions to calculate the total due for all vendors and the total due for each vendor. 
-
-Return these columns:
-
-- The vendor id from the Invoices table The balance due (invoice_total - payment_total - credit_total) for each invoice in the Invoices table with a balance due greater than 0
-- The total balance due for all vendors in the Invoices table The total balance due for each vendor in the Invoices table
-
-Modify the column that contains the balance due for each vendor so it contains a cumulative total by balance due. This should return 11 rows.