can i add a value to a value that is already recorded

[marvaddi]

say that it is recorded that i have 6 quantities of some product in my inventory recorded under column [qty_sold]. And say that i just sold 2 more quantities of that same item. When i come to edit the [qty_sold], instead of doing the math in my head 6+2=8, is there an expression that i can add 2 to that edit and appsheet will do the math and update the value to 8? the expression should be something like input+whats already in the cell? idk, is that possible?

[Joseph_Seddik · Accepted solution]

The expression is simple: new quantity = old quantity + new sales. It is rather more about how you manage your sales records than the expression. 

In your current table, I assume it is related to Inventory or Products, you have a "qty_sold" column for each distinct product. 

You should have a separate table registering your Sales. This Sales table should have a "productID" column that is a Ref to the Products table, and a "Quantity" column. 

You should then setup a Bot through Automation that triggers with the creation of a new Sales row and adds [Quantity] from Sales to [qty_sold] for the corresponding [productID] column in Products table.