Microsoft Excel is packed with useful data management features that don’t see a lot of use, like pivot tables, index and match, and conditional formatting. If you’re just using excel to sum and chart columns, this graphic can show you some other tools to help you become the spreadsheet ninja you always wanted to be.
hàm Group By trong lập trình SQL và cách kết hợp với Count, Sum, Min, Max, AVG
SQL Inner Join Multiple Tables with SUM Tutorial - Use inner joins with multiple tables to create reports. Uses aliases, and the SUM aggregate function to demonstrate the flexibility of the join statement.