@Override
public BlockCursor cursor()
{
if (tupleInfo.getFieldCount() == 1) {
Type type = tupleInfo.getTypes().get(0);
if (type == Type.BOOLEAN) {
return new UncompressedBooleanBlockCursor(positionCount, slice);
}
if (type == Type.FIXED_INT_64) {
return new UncompressedLongBlockCursor(positionCount, slice);