Abstract: Disclosed herein is a computer-implemented method of storing data items arranged in a plurality of columns and a plurality of rows. In some examples the method comprises storing the data items in a segment of persistent storage having a columnstore comprising one or more column files to store the data items column by column, storing the data items in a rowstore in the segment, the rowstore comprising one or more row files to store the data items row by row, and storing a segment index in the segment, the segment index indicating a location in a said column file of the columnstore and a said row file of the rowstore for at least some of the data items.

Abstract: An in-flight entertainment system provides live video/audio programming to passengers and operators over an aircraft video/audio distribution system. The programming signals are derived from satellite broadcast signals that may be in either circular polarized form or linear polarized form. The broadcast signals are collected by two probes and extracted as right and left circular polarized signals. The right and left circular polarized signals are converted into either circular or linear polarized IF signals, and the IF signals are processed by a receiver/decoder unit to produce the live video/audio programming signals.