n between 
every group of two rows it would not take much work from an interested party to 
revert things to their unshuffled state.  
 
Shuffling is rarely effective when used on small amounts of data. For example, if 
there are only 5 rows in a table it probably will not be too difficult to figure out which 
of the shuffled data really belongs to which row. 
 
On the other hand, if a column of numeric data is shuffled, the sum and average of the 
column still work out to the same amount. This can sometime