What are the details of all sales and purchases?
SELECT sales_details FROM sales UNION SELECT purchase_details FROM purchases
SELECT sales_details FROM sales UNION SELECT purchase_details FROM purchases
[{'sales_details': 'a'}, {'sales_details': 'c'}, {'sales_details': 'e'}, {'sales_details': 'f'}, {'sales_details': 'h'}, {'sales_details': 'i'}, {'sales_details': 'l'}, {'sales_details': 'n'}, {'sales_details': 'o'}, {'sales_details': 'p'}, {'sales_details': 'r'}, {'sales_details': 's'}, {'sales_details': 't'}, {'sales_details': 'x'}, {'sales_details': 'y'}, {'sales_details': 'z'}]