The following recipe discusses the creation of flags in the script and the use of these flags in the chart expressions to optimize the calculation speeds.
A flag can be described as a binary status indicator that is used to indicate certain states of data; for example, creating a new field in the table called MonthToDate Flag. This field can be used to flag records with the number 1 if the record was created in the last month, else we mark the record with a 0.
Using this approach, we can now count the number of records in the table that were created in the last month using the expression SUM([Month To Date Flag]).
A flag is often used to code complex decision logic into the load script so that the binary "yes" or "no" decisions can be quickly identified from the calculations.