I'm trying to write sum function in relational algebra with only basic operators without using aggregation function, but I don't know how or if it's possible or not!? I've searched but can't find anything on the internet
For example we have table order:
Code:
OrderID ProductID Quantity
----------------------------
1001 15 5
1002 35 7
1002 10 10
1003 50 30
1004 47 15
We can sum up the quantity with sum function in sql
Code:
SELECT SUM(Quantity) FROM OrderTable
Or
Code:
Fsum(Quantity)(OrderTable)
How can I get the total quantity without using any aggregate functions?