Advantage TDataSet Descendant
Sets when calculated and lookup fields should be populated when using the OnFilterRecord event.
property AdsCalcFieldsBeforeFilter: Boolean default False;
This setting specifies when calculated and lookup fields should be populated when using the OnFilterRecord event. The default value is false, which means the overhead of calculating these fields will not happen until after the OnFilterRecord event has been fired. With this behavior, if the record is filtered out you will save the time it would have taken to populate the calculated fields.
If your OnFilterRecord event uses any of your calculated or lookup fields to perform its task, then you should set the AdsCalcFieldsBeforeFilter property to true.