How_to_retrieve_data_from_two_or_more_tables_2/demo-queries-from slides-14.sql

SELECT 'Active' AS source, invoice_number, invoice_date, invoice_total
    FROM invoices
    WHERE invoice_total - payment_total - credit_total > 0
UNION
    SELECT 'Paid' AS source, invoice_number, invoice_date, invoice_total
    FROM invoices
    WHERE invoice_total - payment_total - credit_total <= 0
ORDER BY invoice_total DESC;

SELECT invoice_number, vendor_name, '33% Payment' AS payment_type,
        invoice_total AS total, invoice_total * 0.333 AS payment
    FROM invoices JOIN vendors
        ON invoices.vendor_id = vendors.vendor_id
    WHERE invoice_total > 10000
UNION
    SELECT invoice_number, vendor_name, '50% Payment' AS payment_type,
        invoice_total AS total, invoice_total * 0.5 AS payment
    FROM invoices JOIN vendors
        ON invoices.vendor_id = vendors.vendor_id
    WHERE invoice_total BETWEEN 500 AND 10000
UNION
    SELECT invoice_number, vendor_name, 'Full amount' AS payment_type,
        invoice_total AS total, invoice_total AS payment
    FROM invoices JOIN vendors
        ON invoices.vendor_id = vendors.vendor_id
    WHERE invoice_total < 500
ORDER BY payment_type, vendor_name, invoice_number;