DSSUM
Sums column values in the given Data Source, optionally filtering rows by formula.
Syntax
DSSUM(dsId, columnIndex, 'optionalFilterFormula')
Example
DSSUM('STAFF', 2) sums the 3rd column's values
Add a filter formula using {{this[column]}} to refer to columns.
DSSUM('STAFF', 2, '{{this[5]}} = "BOB"') sums 3rd column where 6th column = BOBNotes
Refer to the Data Source by it's External Id (from the Data Source -> Settings page).
Refer to the column by it's zero-based index.