I often do large Oracle database queries using FireDAC to analyze registration data about our products and customers. Most of the time I am only processing through millions of rows to create a report or chart. One of the FDQuery properties that I forget to set True is the TDFQuery's "Unidirectional" sub-property found under the FetchOptions (TFDFetchOptions) property.  By default Unidirectional is set to false as some developers will want to put the data into a grid or other container and u...