This MSAccess tutorial explains how to use the Access Sum function with syntax and examples.
The Microsoft Access Sum function returns the sum of a set of numeric values in a select query.
The syntax for the Sum function in MS Access is:
Sum ( expression )
The Sum function can be used in the following versions of Microsoft Access:
You can use the Sum function in a query by clicking on the Totals button in the toolbar (This is the button with the summation symbol). The Sum function is used in conjunction with the Group By clause.
This query would return the sum of all UnitsInStock by ProductName.
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