File file = entry.getValue();
RaptorColumnHandle columnHandle = checkType(entry.getKey(), RaptorColumnHandle.class, "columnHandle");
types.add(columnHandle.getColumnType());
if (file.length() > 0) {
Slice slice = mappedFileCache.getUnchecked(file.getAbsoluteFile());
checkState(file.length() == slice.length(), "File %s, length %s was mapped to Slice length %s", file.getAbsolutePath(), file.length(), slice.length());
// Compute optimal encoding from stats
BlocksFileReader blocks = BlocksFileReader.readBlocks(blockEncodingSerde, slice);
BlocksFileStats stats = blocks.getStats();
boolean rleEncode = stats.getAvgRunLength() > RUN_LENGTH_AVERAGE_CUTOFF;
boolean dicEncode = stats.getUniqueCount() < DICTIONARY_CARDINALITY_CUTOFF;